ENERGY & FUELS
·
2021
·
IF 3.605
Ruzhen Cheng,Run Zou,Long He,Lei Liu,Chang Cao,Xinyuan Li,Xuhong Guo,Jun Xu
The precipitation and deposition of asphaltenes often cause great troubles to the recovery and transportation of crude oil. Adding polymer inhibitors is an effective approach to prevent asphaltenes from clogging. In this study, maleic anhydride-co-octadecene copolymers with imidazolyl, phenyl, and pyridyl pendants were synthesized. The inhibition behaviors of two extracted asphaltenes in the presence of these copolymers were investigated, which were also identified by the rheological tests of the heavy crude oil sample. The chemical structure of both asphaltenes was analyzed by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), elemental analysis, and time-of-flight (TOF) spectrometry. Both asphaltenes A and B have a high aromaticity and low H/C. However, asphaltene B has a much higher aromaticity and polarity than that of asphaltene A. Ultraviolet–visible spectroscopy, turbidity meter, and dynamic light scattering (DLS) were employed to determine the precipitation behaviors of asphaltenes in the absence and presence of copolymers. The influence of intrinsic properties of asphaltenes, polymer concentration, and aromatic group grafting ratio on asphaltene precipitation were also compared. It is found that the initial precipitation point (IPP) of both asphaltenes is increased most by the copolymer containing 2-aminopyridine (PMO-2-P), while the copolymer containing N-(3-aminopropyl)imidazole (PMO-I) shows the worst inhibition performance. It is because that pyridine group has a stronger adsorption capacity with asphaltene than the imidazole group. The effect of various functional groups in copolymers on inhibiting asphaltene precipitation conforms to the following sequence: 2-aminopyridine > aniline > 4-aminopyridine > N-(3-aminopropyl)imidazole. It is also found that high polymer concentration and grafting ratio are beneficial to inhibit the asphaltene precipitation. As a result of the π–π conjugation and hydrogen-bonding attractions between the aromatic groups in the copolymers and the asphaltenes, the polymers can be stably adsorbed onto the surface of the asphaltenes and prevent their aggregation.
研究领域:
石油化学
·
胶体化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2023
·
IF 4.1
Kaixing Luo,Yaya Gao,Yuefei Zhang,Wei Chen,Sheng Tang
In this study, chitosan (CS) and polyacrylic acid (PAA) were used to construct a double-crosslinked network hydrogel, which was employed as the functional material for silica microspheres to prepare a CS/PAA hydrogel modified liquid chromatographic stationary phase. During preparation, octadecene (ODE) was introduced into the CS/PAA hydrogel to improve its hydrophobicity and separation ability. The electrostatic interaction between the amino group of CS and the carboxyl group of PAA effectively prevented the swelling of the CS/PAA hydrogel, which ensured the successful application of the obtained CS/PAA hydrogel@SiO 2 in chromatographic analysis. Polar nucleosides/bases and B-vitamins were selectively separated using hydrophilic interaction liquid chromatography. Hydrophobic polycyclic aromatic hydrocarbons and alkylphenols were effectively separated through reversed-phase liquid chromatography. Moreover, the effective separation of aromatic positional isomers and chiral enantiomers was achieved. This study confirms the potential application of the CS/PAA hydrogel in chromatographic separation. What is noteworthy is that the method developed in this study also provides a feasible strategy to solve the swelling issue associated with the hydrogel-based liquid chromatographic stationary phase.
研究领域:
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Nanomaterials
·
2016
·
IF 1.758
Lina Song,Changzhi Yan,Wei Zhang,Haoan Wu,Zhengyang Jia,Ming Ma,Jun Xie,Ning Gu,Yu Zhang
This study reports the synthesis of three kinds of manganese-doped magnetic ferrite nanoparticles (MnFe2O4) in benzyl ether, octyl ether, and 1-octadecene by a simple and low cost thermal decomposition method. It was found that benzyl ether results in a dramatic improvement in nanoparticle crystallinity owing to its stronger reducibility compared to octyl ether and 1-octadecene, as demonstrated by X-ray diffraction and TEM measurements. Raman spectroscopy detection also indicated that the reducing solvent of benzyl ether was in favor of forming magnetite-like structure ferrite, while maghemite-like structured ferrite was obtained in octyl ether and 1-octadecene. The saturation magnetization () of MnFe2O4 synthesized in benzyl ether was 85 emu/g [Fe], which was 3 and 5 times larger than MnFe2O4 synthesized in octyl ether and 1-octadecene, respectively. The specific absorption rate (SAR) of MnFe2O4 nanoparticles synthesized in benzyl ether was 574 W/g, while MnFe2O4 nanoparticles synthesized in octyl ether and 1-octadecene have had much smaller SAR of 76 and 33 W/g, respectively. MnFe2O4 nanoparticles synthesized in benzyl ether also exhibit higher relaxivity ( mM−1 s−1) than those synthesized in octyl ether and 1-octadecene ( and 22 mM−1 s−1). It was obvious that MnFe2O4 nanoparticles synthesized in reducing benzyl ether have higher crystallinity and thus higher , SAR, and values, which can serve as a better candidate for hyperthermia and magnetic resonance imaging.
研究领域:
材料科学
·
纳米医学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2021
·
IF 4.759
Chao Fan,Kaijun Quan,Jia Chen,Hongdeng Qiu
Three reversed-phase liquid chromatography (RPLC) stationary phases were obtained by using long-chain 1-octadecene (OD) co-grafted with three short-chain monomers, including N-vinylpyrrolidone (NVP), 1-vinylimidazole (VIm) and 4-vinylpyridine (VPy), respectively (noted as Sil@ODNVP, Sil@ODVIm and Sil@ODVPy). Peak broadening phenomenon in RPLC mode which resulted by short-chain was examined carefully. Compared with Sil@ODNVP, both of Sil@ODVIm and Sil@ODVPy had smaller peak width and higher column efficiency in the separation of 10 polycyclic aromatic hydrocarbons (PAHs), 7 alkyl benzenes, 7 aromatic acids, 7 aromatic esters and 9 phenols. In addition, VPy has the strongest ion exchange capacity than other two short-chains. In this case, we can see that VPy and VIm maybe more suitable to be used as functional monomeric modifiers of new chromatographic stationary phases.
研究领域:
分析化学
·
色谱技术
✓ 已验证
DOI
高影响因子
CORROSION
·
2013
·Vol. 69
·期 7
·672-680
·
IF 1.772
Jiang Y.Y.,Chen Y.,Ye Z.Y.,Chen H.,Zhang Z.,Zhang J.Q.,Cao C.N.
N-[2-[(2-aminoethyl) amino] ethyl]-9-octadecenamide (AAOA) has been synthesized in the lab, then tested as an effective and economic acid inhibitor for A3 steel in an acid medium with electrochemical techniques (electrochemical impedance and polarization curve). The results show that AAOA acts as a good mixed-type inhibitor for A3 steel in 1 M hydrochloric acid (HCl) solution, and the inhibition efficiency reaches 94% at the concentration of 200 mg/L. The corrosion current density of A3 steel increases with the increasing temperature from 20°C to 60°C. Meanwhile, Langmuir isotherm is found to provide the description of the adsorption behavior of AAOA, and the value of adsorption free energy (ΔG 0 ) is as low as low as −37.3 kJ/mol. One can assume the adsorption of inhibitor molecules on the metal surface is by chemisorption, which has been understood taking into account some other adsorption parameters (ΔH 0 , ΔS 0 ) and the activation parameters (E a , ΔH * , ΔG * ).
研究领域:
材料科学
·
腐蚀与防护
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Yan-xia Wang,Feng Li,Feng Wang,Yan-feng Pu,Ning Zhao,Fu-kui Xiao
The effects of the polymerization conditions on the yield of insoluble sulfur were investigated by using olefin, such as the 1,-dodecene, 1,-tetradecene, 1,-octadecene as well as acids, such as the salicylic acid, lauric acid and the oleic acid as polymerization stabilizers . The properties of the as-prepared insoluble sulfur were characterized by mu-Raman spectrometer and differential scanning calorimetry (DSC). The results demonstrated that both the olefin and acid stabilizers could couple with the end groups of the IS, thus improved the thermal stability of the IS, and the olefin stabilizers were superior to the acid stabilizers. The stabilizing effect of oleic acid was the best for the acid stabilizers, and the C C in the oleic acid played a crucial role in the stabilization of the IS.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 20
·14456-14468
·
IF 2.993
Dou Qianqian,Wong Ka Wai,Li Yang,Ng Ka Ming
The localized surface plasmon resonance (LSPR) behavior of indium-doped ZnO (IZO) nanocrystals synthesized in different solvents was studied. 1-octadecanol, oleic acid, oleyl alcohol, oleyl amine and 1-octadecene were used as solvent(s) and co-solvent(s) in the pyrolysis synthesis of indium-doped ZnO (IZO) nanoparticles. The results showed that the nanocrystals from a solvent system consisting of 1-octadecene, 1-octadecanol, and oleic acid exhibited enhanced LSPR near-infrared radiation absorption without sacrificing transparency in the visible region. The indium-rich core verified using ICP and XPS analysis was shown to be critical for the enhancement. The reaction mechanism of solvents on the generation of indium-rich core was elucidated through a systematic study of the reaction parameters. The interaction between the activating agent, inhibiting agent and solvent, and their effect on tuning the reactivity of dopant and host precursors were important for the formation of a nanostructure with a dopant-rich core. The solvent effect was also found in the synthesis of gallium-doped ZnO and confirmed to be a general phenomenon in the preparation of doped ZnO nanoparticles.
研究领域:
材料科学
·
纳米技术
·
光学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）