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A benzenesulfonic acid-modified organic polymer monolithic column with reversed-phase/hydrophilic bifunctional selectivity for capillary electrochromatography 被引量:1
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作者 Yikun Liu Ning He +4 位作者 Yingfang Lu Weiqiang Li Xin He Zhentao Li Zilin Chen 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第2期209-215,共7页
Here,a styrene-based polymer monolithic column poly(VBS-co-TAT-co-AHM)with reversed-phase/hydrophilic interaction liquid chromatography(RPLC/HILIC)bifunctional separation mode was success-fully prepared for capillary ... Here,a styrene-based polymer monolithic column poly(VBS-co-TAT-co-AHM)with reversed-phase/hydrophilic interaction liquid chromatography(RPLC/HILIC)bifunctional separation mode was success-fully prepared for capillary electrochromatography by the in situ polymerization of sodium p-styrene sulfonate(VBS)with cross-linkers 3-(acryloyloxy)-2-hydroxypropyl methacrylate(AHM)and 1,3,5-triacryloylhexahydro-1,3,5-triazine(TAT).The preparation conditions of the monolith were optimized.The morphology and formation of the poly(VBS-co-TAT-co-AHM)monolith were confirmed by scanning electron microscopy(SEM)and Fourier transform infrared spectroscopy(FT-IR).The separation perfor-mances of the monolith were evaluated systematically.It should be noted that the incorporation of VBS functional monomer can provideπ-πinteractions,hydrophilic interactions,and ion-exchange in-teractions.Hence,the prepared poly(VBS-co-TAT-co-AHM)monolith can achieve efficient separation of thiourea compounds,benzene series,phenol compounds,aniline compounds and sulfonamides in RPLC or HILIC separation mode.The largest theoretical plate number for N,N0-dimethylthiourea reached 1.7×10^(5)plates/m.In addition,the poly(VBS-co-TAT-co-AHM)monolithic column showed excellent reproducibility and stability.This novel monolithic column has great application value and potential in capillary electrochromatography(CEC). 展开更多
关键词 Sodium p-styrene sulfona Stationary phase monolithic column Capillary electrochromatography Bifunctional interaction
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An enrichment device of silica-based monolithic material and its application to determine micro-carbaryl by NIRS 被引量:3
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作者 Yi Ping Du Xue Mei Wei +2 位作者 Hong Ping Xie Zi Xia Huang Juan Juan Fang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期469-472,共4页
Silica-based monolithic column material was synthesized and an enrichment device was fabricated with the material by assembling the material inside a glass column. The enrichment device was applied for the determinati... Silica-based monolithic column material was synthesized and an enrichment device was fabricated with the material by assembling the material inside a glass column. The enrichment device was applied for the determination of micro-carbaryl with near-infrared spectroscopy (NIRS). The aqueous solutions of carbaryl passed through the device and the carbaryl was enriched on the surface of the material where diffuse reflection NIR spectra were measured. These procedures of enrichment and measurement ensured to concentrate analytes for the measurement, so that the sensitivity of determination of MRS could be improved. NIR spectra of carbaryl solutions (0.01-1.00μg mL^-1), measured after the application of the enrichment device, were pretreated with multiplicative scatter correction (MSC) and regressed against the concentrations of the carbaryl solutions with partial least squares (PLS) method. The results showed that the minimum value of root-mean-square error of prediction (RMSEP) was 0.1771 μg mL^-1 when the number of latent variables was 3 of PLS regression. Therefore, the number of latent variables 3 was selected as the optimum value. RMSEP was not very low but acceptable considering that NIRS is commonly used in macro amount analysis and it is quite difficult for NIRS to determine micro amount analytes, especially, less than 1 μg mL^-1. 展开更多
关键词 Near-infrared spectroscopy (NIRS) PESTICIDE monolithic column ENRICHMENT
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Chiral separation by (S)-naproxen imprinted monolithic column with mixed functional monomers 被引量:9
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作者 Zhen Ying Li Zhao Sheng Liu +1 位作者 Qing Wei Zhang Hong Quan Duan 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第3期322-324,共3页
Molecularly imprinted polymers (MIPs), using (S)-naproxen as template and the combination of butyl methacrylate (BMA) and MAA (1:1 molar ratio) as functional monomers were synthesized by an in situ polymeriza... Molecularly imprinted polymers (MIPs), using (S)-naproxen as template and the combination of butyl methacrylate (BMA) and MAA (1:1 molar ratio) as functional monomers were synthesized by an in situ polymerization reaction. The rendered monolithic column was evaluated in HPLC mode. The result showed that the monolithic MIPs with the combination of two monomers produced better chiral resolution of rac-naproxen (Rs = 1.55) and column efficiencies of imprinted molecules (N = 2860 plates/m) than that with pure MAA. 展开更多
关键词 Molecularly imprinted polymer monolithic column NAPROXEN Chiral separation
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Rapid Preparation of Monolithic Columns for Capillary Electrochromatography Separation 被引量:2
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作者 Wen Jun GONG Yi Jun ZHANG +1 位作者 Yu Ping ZHANG Seong Ho CHOI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期813-816,共4页
Fritless packed silica gel columns were prepared using sol-gel technology, The part of a 75 μm i.d. capillary was filled with a mixture of methacryloxypropyltrimethoxysilane, toluene and hydrochloric acid. Four diffe... Fritless packed silica gel columns were prepared using sol-gel technology, The part of a 75 μm i.d. capillary was filled with a mixture of methacryloxypropyltrimethoxysilane, toluene and hydrochloric acid. Four different photoinitiators such as benzoin methyl ether, Irgacure 819, Irgacure 1700 and Irgacure 1800 were added in the presence or absence of sodium dodecyl sulfate during the polymerization process. The above eight solutions were irradiated at 365 nm about 5-10 min to prepare the porous monolithic sol-gel columns by a one-step process. 展开更多
关键词 monolithic columns ELECTROCHROMATOGRAPHY photopolymerized sol-gel.
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Evaluation of the clenbuterol imprinted monolithic column prepared by reversible addition-fragmentation chain transfer polymerization 被引量:2
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作者 Mamat Turson Xiao Lei Zhuang +2 位作者 Hui Na Liu Ping Jiang Xiang Chao Dong 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1136-1140,共5页
To make more homogenous organic monolithic structure, reversible addition-fragmentation chain transfer (RAFT) process was employed in the synthesis of the clenbuterol imprinted polymer. In the synthesis, the influen... To make more homogenous organic monolithic structure, reversible addition-fragmentation chain transfer (RAFT) process was employed in the synthesis of the clenbuterol imprinted polymer. In the synthesis, the influence of synthetic conditions on the polymer structure and separation efficiency was studied. The result demonstrated that the imprinted columns prepared with RAFT process have higher column efficiency and selectivity than the columns prepared with conventional polymerization in the present study, which may result from the higher surface area, smaller pore size and the narrower globule size distribution in their structures. The result indicated that RAFT polymerization provided better conditions for the clenbuterol imprinted monolithic polymer preparation. 2009 Xiang Chao Dong. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Reversible addition-fragmentation chain transfer polymerization monolithic column Molecularly imprinted polymer CLENBUTEROL
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Determination of phthalate esters in physiological saline solution by monolithic silica spin column extraction method 被引量:2
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作者 Lu Lu Yuki Hashi +2 位作者 Zhi-Hua Wang Yuan Ma Jin- Ming Lin 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第2期92-99,共8页
Monolithic silica spin column extraction (MonoSpin-SPE) was developed as a simple, sensitive, and eco-friendly pretreatment method which combined with ultra-fast liquid chromatography-mass spectrometry (UFLC-MS) t... Monolithic silica spin column extraction (MonoSpin-SPE) was developed as a simple, sensitive, and eco-friendly pretreatment method which combined with ultra-fast liquid chromatography-mass spectrometry (UFLC-MS) to determine the levels of six phthalate esters, dimethyl- (DMP), diethyl- (DEP), dipropyl- [ DPrP], butyl-benzyl- (BBP), dicyclohexyl- (DcHP), and di-n-octyl-(DOP) phthalate in physiological saline samples. Under optimized experimental conditions, the method was linear in the following ranges: 0.2- 50 μg/L for DMP, DEP, DPrP, DcHP and DOP; 5- 100 μg/L for BBP. The correlation coefficients (R2 ) were in the range of 0. 9951 - 0. 9995 for all the analytes and the limits of detection (LODs) and limits of quantification (LOQs) were in the ranges of 0.02 - 0.9 μg/L and 0.08 - 2.7μg/L, respectively. The pretreatment process showed good reproducibility with inter-day and intra-day relative standard deviations (RSDs) below 8.5% and 11.2%, respectively. This method was used to determine the levels of six phthalate esters in physiological saline samples and the recoveries ranged from 71.2% to 107.3%. DMP and DEP were found in actual physical saline samples (brand A and brand B). 展开更多
关键词 monolithic silica spin column phthalate esters physiological saline samples ultra fast liquid chromatography- mass spectrometry (UFLC-MS)
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Novel preparation of organic polymer-based monolithic column by microwave irradiation 被引量:1
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作者 Xiong Wen Ye Yu Ping Zhang +2 位作者 Ling Bo Qu Li Qun Fan Bo Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第11期1399-1402,共4页
Microwave irradiation was firstly attempted for the preparation of organic-based monoliths of poly(styrene-divinylbenzene- methacrylic acid), which single step in situ polymerization was carried out during 15 min. T... Microwave irradiation was firstly attempted for the preparation of organic-based monoliths of poly(styrene-divinylbenzene- methacrylic acid), which single step in situ polymerization was carried out during 15 min. The colunm permeability, electrophoretic and chromatographac behaviors were comparatively evaluated using pressure-assisted CEC, GEC and low pressure-driven separation modes. The largest theoretical plates for the preparing column could be close to 18,0000 plates/m for thiourea in the mode of p-CEC. It provided a viable alternative to traditional initiation means for the perparation of monolithic capillary columns. 展开更多
关键词 monolithic columns Microwave irradiation ELECTROCHROMATOGRAPHY POLYMERIZATION
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Novel preparation of monolithic imprinted columns for electrochromatographic separation by photopolymerization 被引量:1
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作者 Yu Ping Zhang Guo Qiang Zuo +2 位作者 Wen Jun Gong Yue E.Deng Quan Ming Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期734-737,共4页
A monolithic molecularly imprinted polymer with specific recognition ability for 4-hydroxybenzoic acid (4-HBA) was prepared by in situ photopolymerization, using methacrylic acid (MAA) as a functional monomer, ethylen... A monolithic molecularly imprinted polymer with specific recognition ability for 4-hydroxybenzoic acid (4-HBA) was prepared by in situ photopolymerization, using methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EDMA) as a cross-linking agent, toluene and isooctane as porogenic solvents and Irgacure 1800 as an initiator. Baseline separation of isomers of hydroxybenzoic acid was achieved in less than 8 min on this monolithic column using 4-HBA as template, but not on the blank polymer. Furthermore, some neutral compounds could also be baseline-separated on the imprinted polymer column in the mode of pressure-driven capillary electrochromatography. 展开更多
关键词 monolithic columns Molecularly imprinted polymer ELECTROCHROMATOGRAPHY PHOTOPOLYMERIZATION
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Preparation of Polymeric Monolithic Column and Application to the Resolution of Aromatic Compounds in Capillary Electrochromatography 被引量:1
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作者 Xia WANG Wen Zhi LI +4 位作者 Chun Hui LIU Yong Min LI Li Ren CHEN Lanzhou Institute of Chemical Physics Chinese Academy of Sciences, LanZhou 730000 College of Chemistry and Chemical Engeering,Liaocheng University, Liaochang 252059 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第12期1477-1479,共3页
Polymeric monolithic capillary column-poly(GMA-co-EDMA-co-AMPS) was prepared andused for resolution of aromatic compounds (benzalcohol, 2-phenylethanol, toluene, ethylbenzene).
关键词 Polymeric monolithic column aromatic compounds c apillary electrochromatography.
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Determination of L-norvaline and L-tryptophan in dietary supplements by nano-LC using an O-[2-(methacryloyloxy)-ethylcarbamoyl]-10,11- dihydroquinidine-silica hybrid monolithic column 被引量:1
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作者 Dongsheng Xu Elena Sanchez-Lopez +2 位作者 Qiqin Wang Zhengjin Jiang María Luisa Marina 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第1期70-77,共8页
An analytical methodology based on an O-[2-(methacryloyloxy)-ethylcarbamoyl]-10,11-dihydroquinidine(MQD)-silica hybrid monolithic column was developed for the enantioseparation of 9-fluorenylmethoxycarbonyl(FMOC)deriv... An analytical methodology based on an O-[2-(methacryloyloxy)-ethylcarbamoyl]-10,11-dihydroquinidine(MQD)-silica hybrid monolithic column was developed for the enantioseparation of 9-fluorenylmethoxycarbonyl(FMOC)derivatized amino acids by nano-liquid chromatography.The mobile phase was optimized including the apparent pH,content of ACN,and concentration of the buffer to obtain a satisfactory enantioresolution performance.27 FMOC derivatized amino acids including 19 protein and 8 non-protein amino acids were tested,and 19 out of them were enantiomerically discriminated obtaining baseline separation for 11 of them.Analytical characteristics of the method were evaluated for norvaline and tryptophan in terms of linearity,precision,accuracy,limits of detection(LOD)and quantitation(LOQ)showing good performance to be applied to the enantiomeric determination of these amino acids in dietary supplements.LOD and LOQ values were 9.3 and 31 mM for norvaline enantiomers and 7.5 and 25 mM for tryptophan enantiomers,respectively.The contents of D-norvaline and D-tryptophan were below their respective LODs in all the analyzed samples.Quantitation of L-tryptophan and L-norvaline showed good agreement with the labeled contents except for one sample which did not show presence of L-norvaline,contrary to the label indication. 展开更多
关键词 9-Fluorenylmethoxycarbonyl Amino acids Chiral separation NANO-LC Quinidine-silica hybrid monolithic column
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Separation of Inorganic Anions Using Methacrylate-Based Monolithic Column Modified with Trimethylamine in Ion Chromatography Capillary System 被引量:1
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作者 Fitri Mairizki Athika Rahmah +6 位作者   Hilma Radhia Putri Rahmiana Zein Lee Wah Lim Toyohide Takeuchi Edison Munaf 《American Journal of Analytical Chemistry》 2013年第9期451-456,共6页
Methacrylate-based monolithic column was prepared in fused-silica capillary (80 ′ 0.32 mm i.d.) by in situ polymerizetion reaction using glycidyl methacrylate as monomer;ethylene dimethacrylate as crosslinker;1-propa... Methacrylate-based monolithic column was prepared in fused-silica capillary (80 ′ 0.32 mm i.d.) by in situ polymerizetion reaction using glycidyl methacrylate as monomer;ethylene dimethacrylate as crosslinker;1-propanol, 1,4-butanediol, and water as porogenic solvents. The monolith matrix was modified with trimethylamine to create strong anion exchanger via ring opening reaction of epoxy groups. The morphology of the monolithic column was studied by using Scanning Electron Microscope (SEM). This column had good mechanical stability and permeability. The effects of various mobile phases for separation of inorganic anions were investigated. Iodate, bromate, nitrite, bromide, and nitrate were separated within 11 min using100 mMpotassium chloride as mobile phase and detected at 210 nm. This method showed good precision of retention time, acceptable linearity and good sensitivity. Under the optimum condition, the RSD of the retention time was in the range of 1.09%-1.75% (n = 6). The calibration curve showed linear relationships between the peak area and the concentration. The limits of detection (LOD) and the limits of quantitation (LOQ) were between 0.08-0.18 mM and 0.26-0.61 mM, respectively. This method was applied to the determination of inorganic anions in tap water and ground water samples. 展开更多
关键词 Methacrylate-Based monolithic column TRIMETHYLAMINE Ion Chromatography CAPILLARY SYSTEM Inorganic Anions Water Sample
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Preparation Porous Monolithic Column and Its Chromatographic Performance 被引量:3
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作者 Chen Guoliang Zhang Xiaohui +3 位作者 Shang Defa Wang Qingbin Yang Changlong Li Tong 《分析化学》 SCIE EI CAS CSCD 北大核心 2006年第10期1500-1500,共1页
结合连续加料降低聚合体系的放热量,及强化体系的换热能力等措施,实现了无搅拌模式聚合体系中温度分布的均一化.通过单次聚合过程构造了体积为38 mL的大体积整体固定相.SEM及孔隙率分布测试证明了整体固定相具有均匀的孔结构,动态容量... 结合连续加料降低聚合体系的放热量,及强化体系的换热能力等措施,实现了无搅拌模式聚合体系中温度分布的均一化.通过单次聚合过程构造了体积为38 mL的大体积整体固定相.SEM及孔隙率分布测试证明了整体固定相具有均匀的孔结构,动态容量测定及分离蛋白质的实验,表明所制备的径向流动模式整体柱的容量及分辨率不依赖于流速,同时在高流速下具有低背压的特征,可用于生物大分子的分离制备. 展开更多
关键词 整体柱 甲基丙烯酸缩水甘油酯-二甲基丙烯酸乙二酯 温度控制 孔结构 径向流动
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Novel Method of Preparation of Monolithic Columns for Fast Separation byγ-Ray Irradiation
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作者 Yu Ping ZHANG Wen Jun GONG +2 位作者 Li Qun FAN Yi Jun ZHANG Kwang Pill LEE 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第11期1485-1488,共4页
A porous monolithic sol-gel column with the solution of methacryloxypropyltrimethoxysilane in toluene with an acid catalyst was prepared in the presence and absence of sodium dodecyl sulfate. In situ polymerization wa... A porous monolithic sol-gel column with the solution of methacryloxypropyltrimethoxysilane in toluene with an acid catalyst was prepared in the presence and absence of sodium dodecyl sulfate. In situ polymerization was carded out by γ-ray irradiation within the capillary. The γ-radiation-initiated synthesis could generate radicals directly on the monomer avoiding use of any initiator. The chromatographic behavior of the capillary monolithic columns were studied in the modes of CEC, p-CEC and low pressure-driven separation, all the tests exhibited reversed-phase character. It provided a viable alternative to either thermally initiated or photo polymerization method for the preparation of monolithic columns. 展开更多
关键词 monolithic columns ELECTROCHROMATOGRAPHY γ-ray irradiation polymerization.
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Preparation of Monolithic Column and Its Application in p-CEC
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作者 JunJiaoYANG KaiZHANG +2 位作者 RuYuGAO YuKuiZHANG ChaoYAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第4期435-438,共4页
A novel monolithic stationary phase having long alkyl chain ligands was introduced and evaluated in pressurized-capillary electrochromatography of small neutral and charged compounds. The monolithic column was prepare... A novel monolithic stationary phase having long alkyl chain ligands was introduced and evaluated in pressurized-capillary electrochromatography of small neutral and charged compounds. The monolithic column was prepared by the in situ copolymerization of ethylene dimethacrylate, 1-hexadecene, allyl alcohol and 2-acrylamido-2-methyl-1-propanesulfonic acid in a quaternary porogenic solvent mixture consisting of 1, 4-butanediol, cyclohexanol, dodecanol and water. 展开更多
关键词 monolithic column p-CEC aromatic compounds.
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Fast preparation of photopolymerized monolithic columns for capillary electrochromatography
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作者 龚文君 许光日 +3 位作者 张毅军 张裕平 CHOI Seong-ho LEE Kwang-pill 《Journal of Central South University of Technology》 EI 2008年第2期176-182,共7页
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
关键词 ELECTROCHROMATOGRAPHY monolithic columns photopolymerized sol-gel aromatic hydrocarbons
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二十辊轧机的结构特点和应用发展
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作者 李守卫 《山西冶金》 CAS 2024年第5期66-69,74,共5页
通过研究引进的各类型二十辊轧机,分析比较其结构特点及实际应用情况,理清二十辊轧机的技术发展脉络,为二十辊轧机的选型、开发提供参考。以国内引进的整体式、四立柱式和分体式二十辊轧机为研究对象,分析了各类型二十辊轧机的结构特点... 通过研究引进的各类型二十辊轧机,分析比较其结构特点及实际应用情况,理清二十辊轧机的技术发展脉络,为二十辊轧机的选型、开发提供参考。以国内引进的整体式、四立柱式和分体式二十辊轧机为研究对象,分析了各类型二十辊轧机的结构特点以及相互联系,结合在不锈钢、硅钢轧制领域的实际使用情况,阐明了各型轧机具有的优点和缺点。国产二十辊轧机打破了引进型轧机的垄断局面,并迅速发展,为生产企业提供了更多选择空间。对于生产企业来说,整体式二十辊轧机依然是性价比较高的选择,考虑到不同的原料和产品的定位,可以采取整体式二十辊与四立柱式、分体式二十辊轧机相互配合的选型方案。 展开更多
关键词 二十辊轧机 整体式 四立柱式 分体式
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基于MCM41掺杂的萘普生印迹整体柱的制备及研究
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作者 赵丽丽 孟鑫 +2 位作者 贾明之 黄艳萍 刘照胜 《广东化工》 CAS 2024年第7期62-65,共4页
本研究通过分子印迹技术以原位聚合法成功合成了MCM41-MPS掺杂的萘普生印迹整体柱。通过改进配方进而考察色谱条件,实现印迹因子最高达10.7,相比未掺杂MCM41-MPS的印迹整体柱,印迹因子提高两倍多。结果表明,MCM41-MPSMIP比MIP具有更高... 本研究通过分子印迹技术以原位聚合法成功合成了MCM41-MPS掺杂的萘普生印迹整体柱。通过改进配方进而考察色谱条件,实现印迹因子最高达10.7,相比未掺杂MCM41-MPS的印迹整体柱,印迹因子提高两倍多。结果表明,MCM41-MPSMIP比MIP具有更高的保留因子和印迹因子,并通过傅立叶红外吸收光谱(FT-IR)和扫描电子显微镜(SEM)对聚合物进行表征,采用Langmuir拟合得到MCM41-MPS MIP的最大吸附量为10.89 mg/g,最终,对湖水中加标的萘普生进行固相萃取,回收率达96.40%。 展开更多
关键词 MCM41 萘普生 分子印迹整体柱 吸附富集
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Cu_(7)Zn_(2)双金属簇整体柱制备及其液相色谱分离性能研究
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作者 金什琦 褚琪琪 陈怀侠 《湖北大学学报(自然科学版)》 CAS 2024年第6期855-863,共9页
在高效液相色谱不锈钢分离柱(150 mm×4.6 mm)内制备了Cu_(7)Zn_(2)双金属簇共聚整体柱,并考察了其分离性能。分别选择邻苯二甲酸酯类和多环芳烃为分析物,对Cu_(7)Zn_(2)双金属簇色谱柱进行分离性能研究和吸附机理探讨。结果表明,Cu... 在高效液相色谱不锈钢分离柱(150 mm×4.6 mm)内制备了Cu_(7)Zn_(2)双金属簇共聚整体柱,并考察了其分离性能。分别选择邻苯二甲酸酯类和多环芳烃为分析物,对Cu_(7)Zn_(2)双金属簇色谱柱进行分离性能研究和吸附机理探讨。结果表明,Cu_(7)Zn_(2)双金属簇整体柱与商品化C 18色谱柱相比分离速度更快,10 min内即可实现分析物的快速分离。同时Cu_(7)Zn_(2)双金属簇整体柱具有反相色谱柱的分离特点,吸附机理推测为疏水作用和π-π堆积作用。针间(n=10)、日间(n=5)和柱间(n=3)保留时间的重复性(RSDs)在0.8%~1.9%范围内,峰面积的重复性(RSDs)为1.3%~3.9%。因此,Cu_(7)Zn_(2)双金属簇共聚整体柱具有良好的高效液相色谱分离重复性和稳定性。 展开更多
关键词 Cu_(7)Zn_(2)双金属簇 共聚整体柱 色谱柱
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半制备整体柱液相色谱法测定食品中泛酸的含量
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作者 陈汉峰 杨静 +2 位作者 黎俊威 侯少平 刘春丽 《食品安全导刊》 2024年第31期79-83,共5页
目的:建立半制备整体柱液相色谱法测定食品中泛酸含量的分析方法。方法:样品中泛酸用热水提取,以磷酸二氢钾溶液和乙腈为流动相,流速2 mL·min^(-1),进样量500μL,柱温30℃,检测波长200 nm,经Merck半制备整体柱净化,在泛酸出峰处收... 目的:建立半制备整体柱液相色谱法测定食品中泛酸含量的分析方法。方法:样品中泛酸用热水提取,以磷酸二氢钾溶液和乙腈为流动相,流速2 mL·min^(-1),进样量500μL,柱温30℃,检测波长200 nm,经Merck半制备整体柱净化,在泛酸出峰处收集溶液,收集液经反相C18柱定量分析。结果:泛酸浓度在0.001~0.032μg·L^(-1)具有良好的线性关系,相关系数为0.9999,方法检出限为0.025 mg/100 g,定量限为0.08 mg/100 g,泛酸在食品中测定结果的相对标准偏差为2.4%~3.6%,加标回收率均大于90%。结论:针对含有蛋白、肽、淀粉等复杂基质的食品,本半制备整体柱液相色谱法的检测一致性较好,分离度、精密度、准确性等均符合要求。有效解决复杂基质、杂质干扰下目标峰难分离、检测结果不稳定、平行差的问题。 展开更多
关键词 高效液相色谱 泛酸 半制备整体柱
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Seismic behavior of precast segmental column bridges under near-fault forward-directivity ground motions 被引量:1
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作者 Xin Lifeng Li Xiaozhen +1 位作者 Fu Peiyao Mu Di 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2022年第2期559-571,共13页
Precast segmental column bridges exhibit various construction advantages in comparison to traditional monolithic column bridges.However,the lack of cognitions on seismic behaviors has seriously restricted their applic... Precast segmental column bridges exhibit various construction advantages in comparison to traditional monolithic column bridges.However,the lack of cognitions on seismic behaviors has seriously restricted their applications and developments.In this paper,comprehensive investigations are conducted to analyze the dynamic characteristics of precast segmental column bridges under near-fault,forward-directivity ground motions.First,the finite-element models of two comparable bridges with precast segmental columns and monolithic columns are constructed by using OpenSees software,and the nonlinearities of the bridges are considered.Next,three different earthquake loadings are meticulously set up to handle engineering problems,namely recorded near-and far-field ground motions,parameterized pulses,and pulse and residual components extracted from real records.Finally,based on the models and earthquake sets,extensive explorations are carried out.The results show that near-fault forward-directivity ground motions are more threatening than far-field ones;precast segmental column bridges may suffer more pounding impacts than monolithic bridges;the“narrow band”effect caused by near-fault,forward-directivity ground motions may occur in bridges with shorter periods than pulse periods;and pulse and residual components play different roles in seismic responses. 展开更多
关键词 precast segmental column bridge monolithic column bridge seismic behavior near-fault forward-directivity ground motion pounding effect
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