ENERGY & FUELS
·
2021
·
IF 3.605
Xuechun Ding,Shengchao Wei,He Bian,Lijun Zhu,Daohong Xia
Despite the studies on asphaltene aggregation throughout few decades, the formation of asphaltene aggregates and subsequent deposition are still the biggest challenges in the oil industry. Especially, the role of porphyrins existing in oil naturally on asphaltene aggregation is not completely understood due to asphaltene’s and porphyrin’s special structures. Herein, we investigated the influence of tetraphenylporphyrin (TPP), nickel tetraphenylporphyrin (NiTPP), and vanadium tetraphenylporphyrin (VOTPP) on asphaltene aggregation by a multiscale approach, which provides an in-depth understanding of the role of porphyrins on asphaltene aggregation. UV–vis spectroscopy and fluorescence spectroscopy were performed to examine the self-aggregation of TPP, NiTPP, and VOTPP and the influence of porphyrins on the aggregation of asphaltene. The changes of stacking structures, microscopic structures, and particle size distributions of co-aggregates of asphaltenes with porphyrins were analyzed in detail via X-ray diffraction, inverted fluorescence microscopy, and granulometric distribution, respectively. The characterization results indicated that the aggregation ability of the porphyrins (TPP, NiTPP, and VOTPP) was stronger than that of asphaltene and porphyrins can promote the aggregation of asphaltene, which leads to the increase of the average aromatic sheet number, aggregation morphology, and particle size of asphaltene aggregates. Based on experimental analysis, the possible mechanism by which porphyrins promoted asphaltene aggregation was elucidated. This research provided new insights into the aggregation and disaggregation of asphaltenes.
研究领域:
石油化学
·
材料科学
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产品关联
DOI
高影响因子
ZEITSCHRIFT FUR KRISTALLOGRAPHIE-NEW CRYSTAL STRUCTURES
·
2022
·Vol. 238
·期 1
·13-14
·
IF 0.365
Zhihong Zhu,Lilei Zhang
C 14 H 12 BrClN 2 O, monoclinic, P 2 1 / c (no. 14), a = 13.4072(6) Å, b = 8.6103(5) Å, c = 12.3824(6) Å, β = 100.475(4), V = 1405.60(12) Å 3 , Z = 4, R gt
( F ) = 0.0499, wR ref
( F
2 ) = 0.1215, T = 173 K.
研究领域:
化学
·
晶体学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2022
·
IF 9.221
Yuhuan Zhang,Hongjuan Li,Shiguo Sun,Yongqian Xu
Triphenylphosphine (PPh 3 ) and tetrakis(triphenylphosphine)palladium (Pd(PPh 3 ) 4 ) are harmful at extremely low concentration, thus it is essential to explore selective and sensitive method to detect them. Based on Staudinger reaction mechanism, here we present a simple excited-state intramolecular proton transfer (ESIPT) fluorescent probe (HBTN) for detection of PPh 3 and Pd(PPh 3 ) 4 over other phosphine derivatives with differential channel fluorescence (enol and keto emission). The reaction-typed fluorescence probe with novel Staudinger reaction mechanism offers very low autofluorescence and a large signal-to-noise response signal, which is beneficial for the sensitive detection of PPh 3 and Pd(PPh 3 ) 4 . Moreover, HBTN can be used for efficiently detecting Pd(PPh 3 ) 4 residues in highly purified products and imaging PPh 3 in living cells.
研究领域:
分析化学
·
生物医学
✓ 已验证
DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 5
·903
·
IF 4.967
Zhe Liu,Hua Wang,Chuanjian Zhou
An elastomer with mechanical adaptability is a new kind of polymer material in which the increasing stress under continuous deformation is significantly inhibited in a large deformation area. Liquid crystal-based organosilicone elastomers, which can dissipate energy through reversible internal phase transition under external stimulation and have recoverable large deformation capacity, have drawn much interest as mechanical adaptability materials. However, there is no good way to control the mechanical adaptability at present. For this purpose, we prepared a new liquid crystal-based phenyl silicone rubber (LCMVPQ) using two-step click reactions and systematically explored the effect of phenyl content on its mechanical adaptability to achieve the regulation of mechanical adaptability. With an increase in phenyl content in the LCMVPQs, phenyl can hinder the rearrangement of the mesogenic units along the applied stress direction, which enables the adjustment of mechanical adaptability to meet the needs of different situations. In addition, the introduction of the liquid crystal phase impedes the internal friction of the molecular chain movement of the LCMVPQs and reduces the damping performance of silicone rubber. This research achieves the regulation of elastomers with mechanical adaptability and is expected to be applied in practical application fields.Keywords:liquid crystal-based phenyl silicone rubber;phenyl content;the regulation of mechanical adaptability;damping performance
研究领域:
高分子科学
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材料科学
·
机械工程
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2018
·
IF 5.123
Yinhui Yang,Zhengfeng Chang,Xiaohong Yang,Meiling Qi,Jinliang Wang
Herein we report a propeller-like hexaphenylbenzene-based hydrocarbon material (denoted as BT) as the stationary phase for capillary gas chromatography (GC). The statically-coated BT capillary column showed a high column efficiency of 4340 plates m −1 and weak polarity. Owing to its unique conformation, π-electron toroidal delocalization and intrinsic microporosity , the BT stationary phase exhibited interesting selectivity for aromatic compounds over alkanes. Compared with the graphene (G) column, the BT column showed much prolonged retention and high selectivity for aromatic isomers, especially methylnaphthalenes , dimethylnaphthalenes and phenanthrene/anthracene, mainly because of its propeller-like conformation with rich intercalation effects. Moreover, it exhibited good column repeatability (intra-day, inter-day) and reproducibility (between-column) with RSD values on the retention times less than 0.08% for intra-day, 0.32% for inter-day and 3.8% for between-column, respectively. Also, it showed good potential for determination of minor isomer impurities in real samples. To the best of our knowledge, this work presents the first example of employing an neat aromatic hydrocarbon material as the GC stationary phase with high selectivity for analytes of a wide ranging polarity.
研究领域:
分析化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2015
·Vol. 33
·期 8
·939-947
·
IF 1.578
Guo-Feng Zhang,Tao Chen,Ze-Qiang Chen,Matthew P. Aldred,Xianggao Meng,Ming-Qiang Zhu
We have synthesized a series of fluorene-based fluorophores, in which a central fluorene core has been modified with different peripheral arylene vinylene substituents that are able to activate aggregation-induced emission (AIE) characteristics. 9,9-Dioctylfluorene doubly end-capped at the 2,7-positions with triphenylethene groups, such as 4-(2,2-diphenylvinyl)phenyl (F1-(2,2)-HTPE) and 4-(1,2-diphenylvinyl)phenyl (F1-(1,2)-HTPE) were synthesized and compared to the tetraphenylethene analogue (F1-TPE). Both F1-(2,2)-HTPE and F1-(1,2)-HTPE glow with a deep blue fluorescence in THF solution with emission maxima ( λ em ) of 426 and 403 nm, respectively. The λ em slightly red-shifts in the solid-state to 458 nm for F1-(2,2)-HTPE and 437 nm for F1-(1,2)-HTPE. The fluorescence quantum yields ( ø F ) of F1-(2,2)-HTPE ( ø F =35.1 %) and F1-(1,2)-HTPE ( ø F =26.2%) were found to be higher in solution compared to the near quenching of F1-TPE ( ø F =0.1%). Consequently, this results in weaker AIE-stability of F1-(2,2)-HTPE ( α AIE =1.5) and F1-(1,2)-HTPE ( α AIE =1.9) compared to F1-TPE ( α AIE =125), suggesting that four phenyl groups are necessary for efficient AIE-activity of these fluorene bridged arylene vinylene type materials. In addition, decreasing the steric hindrance around the arylene vinylene moiety by removal of a phenyl ring is another method to decrease the AIE characteristics, in a similar manner to the commonly known "phenyl-locking". Non-polar triphenylethenes are poorer AIE materials than their tetraphenylethene analogues. Replacing the hydrogen atom of F1-(2,2)-HTPE with a cyano group affords fluorene end-capped with 2,3,3-triphenylacrylonitrile (F1-TPAN), which boosts the AIE-effect to α AIE =90.5 and red-shifts the solid-state emission ( λ em =528 nm) with near quenching in THF solution ( ø F =0.12%). X-ray crystallographic analysis of F1-TPAN indicates that the introduction of cyano groups can not only diminish the intramolecular steric hindrance in comparison of F1-TPE, but also improve the molecular cohesion ability via multiple C H···N interactions.
研究领域:
有机化学
·
材料科学
·
光学
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DOI
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2015
·Vol. 178
·期 3
·558-575
·
IF 1.735
Liang Jiayuan,Zhang Yun,Sun Aijun,Deng Dun,Hu Yunfeng
A novel microbial esterase BSE01281 identified from the Indian Ocean was cloned, expressed, and functionally characterized. Esterase BSE01281 could enanoselectively resolve (±)-1-phenylethanol and (±)-1-phenylethyl acetate through two types of enzymatic reactions. After the optimization of enzymatic reactions, BSE01281 could efficiently generate ( R )-1-phenylethyl acetate with high enantiomeric excess (>99 %) and high conversion (42 %) after 96 h trans-esterification reactions. Additionally, BSE01281 could also produce ( R )-1-phenylethanol ( e.e . > 99 %) and ( S )-1-phenylethyl acetate ( e.e . > 95 %) at a conversion of 49 % through direct hydrolysis of inexpensive racemic 1-phenylethyl acetate for 8 h. Optically pure ( R )-1-phenylethanol generated from direct enzymatic hydrolysis of racemic 1-phenylethyl acetate by BSE01281 is not easily prepared by dehydrogenases, which generally follow the “Prelog’s rule” and give ( S )-1-phenylethanol instead.
研究领域:
生物化学
·
酶工程
·
合成生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2018
·Vol. 56
·期 20
·2280-2285
·
IF 2.588
Dao-Guang Teng,Xian-Yong Wei,Zheng Yang,Zhi-Min Zong
Thermostable and fluorescent poly(phenylene methylene) (PPM) was synthesized via α-Fe 2 O 3 /attapulgite (α-Fe 2 O 3 / A )-mediated polymerization of benzyl chloride (BC) in CCl 4 in good yields. A carbocationic mechanism was proposed based on the controlling experiment. The structure and properties of PPM were characterized by Fourier transform infrared spectrometry, 1 H and 13 C nuclear magnetic resonance spectrometry, thermogravimetric analysis, elemental analysis, gel permeation chromatography, and UV–vis and fluorescence spectrometry. The results show that PPM possesses outstanding homoconjugation fluorescence and excellent thermal stability with onset decomposition temperature of ca. 420 °C. Recycled α-Fe 2 O 3 / A proved to be still highly active for BC polymerization. Moreover, the strategy features low-cost and readily accessible starting materials, simple one-pot operation, and recyclable catalyst, facilitating future applications. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56 , 2280–2285
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Jing Hu,Yu-Hang Zhang,Wei Chen,Zheng-Wu Bai
In order to covert azidoamylose into ureidoamylose derivatives in a facile way, 6-azido-6-deoxyamylose was reacted with triphenylphosphine , and then with water and a phenyl isocyanate in turn. The obtained product was amylose 2,3-bis(phenylcarbamate)-6-deoxy-6-(phenylurea), which was synthesized through three reactions in a one-pot method. The essential point to ensure the method be successful was that the water should be fed at an appropriate amount. The prepared amylose 2,3-bis(phenylcarbamate)-6-deoxy-6-(phenylurea)s were characterized by FT-IR, 1 H NMR and elemental analysis , substantiating the reduction of the azido group and the subsequent derivatization of the resulted amino group and the hydroxyl group in amylose were fully performed. In addition, the amylose 2,3-bis(phenylcarbamate)-6-deoxy-6-(phenylurea)s were coated on macroporous 3-aminopropyl silica gel to afford chiral stationary phases (CSPs) for high-performance liquid chromatography. The enantioseparations of the CSPs were evaluated, and the results indicated that the CSPs possessed chiral recognition ability towards some chiral compounds.
研究领域:
有机化学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2016
·Vol. 134
·期 8
·
IF 1.866
Xiaobing Hu
In this thesis, two novel porous hyperbranched poly(1,3,5-tris(4-carboxyphenyl) benzene p -phenylenediamine) amides with different terminal functional groups are synthesized through an A 2 + B 3 approach using 1,3,5-tri(4-carboxyl phenyl) benzene (H 3 BTB) and p -phenylenediamine as raw material, N -methyl-pyrrolidone as solvent, triphenyl phosphite and pyridine as dehydrating agent, by means of regulating the mole ratio of the monomers. The chemical structures of the prepared hyperbranched polymers are characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance ( 1 H-NMR and 13 C-NMR) analysis. These two polymers can be soluble in dimethyl sulfoxide (DMSO) and N , N -dimethyl formamide (DMF). Their DMSO solutions exhibit strong blue fluorescence, especially for the amino terminated polymer HP-NH 2 . While in DMF solution, the two polymers emit strong green fluorescence. These two polymers are porous polymers with the Brunauer−Emmett−Teller surface areas of 4.53 and 24.52 m 2 /g for HP-COOH and HP-NH 2 , respectively. They are potential useful in the areas of storage, separation, catalysis, and light emitting. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44505.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2021
·
IF 2.694
Qing Yi,Wei-Peng Chen,Xiang-yang Zhang,Yan-Yang Wu,Bin Wu,Kui Chen,Li-Jun Ji
The isobaric vapor–liquid equilibrium (VLE) data of 2-phenylethanol (2-PE) + 2-ethylphenol (2-EP), 1-phenyl-2-propanol (1,2-PP) + 2-ethylphenol (2-EP), 2-phenylethanol (2-PE) + 1-phenyl-2-propanol (1,2-PP) and 2-phenyl-1-propanol (2,1-PP) + 2-ethylphenol (2-EP) were measured by a modified Rose type still under 101.3 kPa. Both the Fredenslund test and Redlich–Kister area test were employed to verify the consistency of the experimental data. Besides, the experimental isobaric VLE data were correlated by Wilson, nonrandom two-liquid, and universal quasi-chemical models, and the corresponding parameters were obtained accordingly. All three models showed good agreement with the experimental data, and among which the Wilson model performed slightly better than the others.
研究领域:
化学工程
·
物理化学
✓ 已验证
DOI
高影响因子
GEODERMA
·
2015
·
IF 2.772
Meng Zhu,Chen Tu,Haibo Zhang,Yongming Luo,Peter Christie
A solvent extraction method coupled to high-performance liquid chromatography with tandem mass spectrometry detection (HPLC–MS/MS) was developed and validated for the simultaneous determination of soil diphenylarsinic acid (DPAA) and phenylarsinic acid (PAA). Several extraction solvents were evaluated with respect to the degree of soil extract-induced matrix effects and the recovery values for DPAA and PAA in the four studied soil matrices. Validation data showed that solvent extraction had a negligible impact on the accurate quantification of DPAA. In contrast, only with disodium hydrogen phosphate extraction did the method give both limited matrix effects (102–107%) with a coefficient of variation < 3% ( n = 4) and efficient recoveries (77–109%) at two spiking levels (20 and 50 mg kg − 1 ) for PAA. The selection of an appropriate extractant was the approach to reduce matrix effects while guaranteeing satisfactory recoveries of soil DPAA and PAA. Chromatographic separation was completed in 37 min and the analytes were detected in positive mode using selected reaction monitoring . MS/MS operating conditions were optimized for both electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) sources. Under optimal conditions the detection limit was 0.01 and 1.00 μg L − 1 for DPAA and PAA. The method detection limits (MDLs) obtained ranged from 2.52 to 3.42 μg kg − 1 for DPAA and from 0.23 to 0.33 mg kg − 1 for PAA depending on the soil types, and the intraday and interday precision was less than 5% for both analytes at two different concentrations. The method was successfully applied for the simultaneous determination of DPAA and PAA in one-month aged soils, satisfactory recoveries (> 74.03%) were obtained for both analytes. The results show that the proposed solvent extraction method coupled to HPLC–MS/MS analysis can provide accurate and reliable determinations of DPAA and PAA in soil samples.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）