CHINESE JOURNAL OF POLYMER SCIENCE
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2021
·Vol. 39
·期 9
·1211-1216
·
IF 3.603
Xiang Ming-Yue,Lyu Dong,Liu Ling-Zhi,Men Yong-Feng
Crystallinity of bottlebrush polymers due to side chain crystallization has been considered to be related to the length of the side chains only under the assumption of complete participation of crystallization by all side chains. Recent experimental results revealed that in poly( n -alkyl methacrylate)s a fraction of side chains could not crystallize due to constraints imposed by the trapped main chain entanglements and required expansion of main chain-main chain distance. This result renders the original simplified consideration of the origin of crystallinity in bottlebrush polymers questionable. In this work, we introduce a new parameter f c , the fraction of crystallizable side chains, to better describe the crystallinity of bottlebrush polymers. A linear relationship between the melting enthalpy and the number of alkyl groups in side chains for bottlebrush polymers reported repeatedly indicates that f c remains essentially unchanged when bottlebrush polymers had the same main chain structure and grafting degree but different side chain lengths. The slope of the above-mentioned linear relationship is thus \(\Delta H_{\text{CH}_2}\times f_{c}\) , where \(\Delta H_{\text{CH}_2}\) stands for the melting enthalpy of one mole alkyl group packed into the crystal. With a known value of f c , it is possible to estimate the value of \(\Delta H_{\text{CH}_2}\) . In case of poly( n -alkyl methacrylate)s, we estimated \(\Delta H_{\text{CH}_2}\) of hexagonal crystal being at most 5.74 kJ/mol with the knowledge of possibly smallest f c of 0.67 obtained from small angle X-ray scattering data. Therefore, the crystallinity of bottlebrush polymer would be calculated based on the equation \(X_{\rm{c}}=f_{\rm{c}}\times\frac{N_{\rm{c}}}{N}\) with N and N c being the number of alkyl groups in a side chain and those packed in the crystalline structure, respectively. Both chemical structure and grafting degree of bottlebrush polymers affect f c .
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JOURNAL OF SURFACTANTS AND DETERGENTS
·
2010
·Vol. 14
·期 3
·317-324
·
IF 0.795
Cui Zheng-gang,Song Hong-xing,Yu Jun-jie,Jiang Jian-zhong,Wang Feng
Alkali-surfactant-polymer (ASP) flooding has been considered to be one of the useful tertiary oil recovery techniques. However, field tests in China have revealed that serious side effects may occur due to using alkali. Thus alkali-free SP flooding is more favorable in China. Unfortunately, surfactants effective in ASP flooding are usually ineffective in the absence of alkali and new surfactants need to be designed. In this paper N -(3-Oxapropanoxyl)dodecanamide as a pure compound and a mixture of homologues with narrow EO number distribution, synthesized by the reaction of lauroyl chloride with diglycolamine and addition of one ethylene oxide to coconut monoethanolamide respectively, are examined for their adaptability in SP flooding. It is found that, when mixed with betaines, both products can reduce Daqing crude oil/connate water interfacial tension to a magnitude of 10 −3 –10 −4 mNm −1 at 45 °C in a wide surfactant concentration range, 0.01–0.5 wt%, and oil displacement tests using natural cores indicates that a tertiary oil recovery of 18.6 ± 0.4% OOIP can be achieved by SP flooding with the N -(3-Oxapropanoxyl)dodecanamide as the main surfactant without adding any alkaline agent and neutral electrolyte. N -(3-Oxapropanoxyl)dodecanamide, as a nonionic surfactant without a cloud point and producible industrially from renewable materials, is an ideal surfactant for SP flooding in the absence of an alkaline agent.
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JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION
·
2017
·
IF 1.9
Kwanghyok Jong,Benzhi Ju,Shufen Zhang
In this study, a novel type of pH-responsive polymer PyHES-NAC (2-hydroxy-3-(2-propynyloxy) propyl hydroxyethyl starch (PyHES)) – (N-acetyl-cysteine (NAC)) was synthesized. First, PyHES was prepared via hydrophobic modification of hydroxyl groups in hydroxyethyl starch (HES) with propynylglycidyl ether (PGE), and then pH-responsive carboxylic acid group was connected to propynyl group via thiol-yne click reaction with NAC. Aqueous PyHES-NAC solutions exhibited a good transference between hydrophobic (or self-assembly) and hydrophilic static along with the change of pH value and protective properties of drugs under acidic conditions. 10.0% DOX was released under artificial gastric fluid after 2 h, whereas an immediate release (above 80%) was observed under artificial intestinal fluid. Drug loading capacity of PyHES-NAC was increased by the increase of degree of substitution (DS) of hydrophobic propynyl groups in PyHES, and 41 wt% DOX Loading capacity was the highest value in our study area.
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PHYSICS OF FLUIDS
·
2021
·Vol. 33
·期 2
·
IF 3.521
Zhao Wenjing,Ma Hongzhi,Ji Wenjie,Li Weibin,Wang Jin,Yuan Quanzi,Wang Yuren,Lan Ding
Flows of thin fluid layers spreading, which have a distinguished history, have been studied since the days of Reynolds, who was among the early researchers to examine flows. Different from surfactant-driven spreading, which is currently the most common subject of study, we observe the spreading process of n -hexadecane driven by volatile silicone oil at the surface of the aqueous substrates and explore the influence of Marangoni flow caused by surface tension gradient on liquid-driven spreading. We find that on different substrates, the initial state of n -hexadecane is different, and there are two instability patterns during the spreading, subsequently, which are analyzed theoretically. While the n -hexadecane drop stationed on the liquid surface is small, it is driven to form a rim and then breaks up into beads, which shows the Rayleigh–Plateau instability patterns. When we put the n -hexadecane drop on the surface of the saturated sodium chloride solution, which spreads out more, it is driven to form a circular belt first and fingering instability subsequently occurs at the inner edge of the circular belt.
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CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Zhihua Zhao,Yang Dong,Xianghao Meng,Peijuan Wu,Jichao Wang
The present work focuses on developing a high-performance n-butanol detection system through heterojunction engineering of W 18 O 49 /CeO 2 nanocomposites, aiming to achieve superior sensitivity and selectivity in volatile organic compound monitoring. The solvothermal-mediated fabrication of CeO 2 nanocrystals served as the foundation for hierarchical assembly of the W 18 O 49 /CeO 2 heterostructured sensing layer. A comprehensive investigation was organized, encompassing discriminative selectivity analysis, durability testing, response profiling, response/recovery characterization under prolonged operational conditions. Experiment confirmed that the W 18 O 49 /CeO 2 heterojunction sensor achieved peak analytical performance at room temperature, exhibiting a response of 12.2 when exposed with 100 ppm n-butanol. In contrast, the pristine W 18 O 49 had a response of 2.6, and pristine CeO 2 showed negligible response. DFT results showed that the adsorption energy of n-butanol on the W 18 O 49 /CeO 2 composite was −1.092 eV, which was much stronger than that on pristine W 18 O 49 (−0.305 eV), indicating a more favorable adsorption process. Notably, the sensor achieved a detection threshold of 1 ppm n-butanol with a response magnitude reaching 23.5 %, indicating its capability for ultra-trace gas analysis. Collectively, these findings substantiate the W 18 O 49 /CeO 2 heterojunction architecture as a highly effective sensing platform for volatile organic compound (VOC) detection, with particular applicability to n-butanol gas monitoring in smart manufacturing environments. The superior sensing efficacy stems from the synergistic charge transfer mechanism at the heterointerface, validated by both experimental characterization and theoretical modeling.
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ANALYTICAL CHEMISTRY
·
2025
·
IF 6.7
Yueyue Li,Yisheng Wang,Yingying Xiong,Xuejiao Liu,Yang Li,Ying Zhang,Haojie Lu
Human serum albumin (HSA), the most abundant plasma protein predominantly synthesized and secreted by the liver, harbors atypical N-glycosylation modifications at Asn68 and Asn123. Despite their potential biological relevance, the comprehensive characterization of these modifications remains limited. Here, we systematically characterized atypical N-glycosylation on HSA using a sialic acid linkage-specific derivatization strategy coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), identifying 35 N-glycans including 23 sialylated N-glycans distinguished sialic acid linkage isomers. LC-ESI-MS analysis further resolved 25 site-specific N-glycopeptides, establishing the most detailed HSA N-glycosylation profile to date and elucidating its structural diversity. Given the liver-specific origin of HSA, we further explored the clinical relevance of HSA glycosylation in serum samples from healthy controls (HC), liver cirrhosis (LC), and hepatocellular carcinoma (HCC) patients and found that HSA glycopeptides exhibited exceptional diagnostic accuracy in distinguishing LC from HCC patients (AUC = 0.906). These findings not only decode the complexity of HSA glycosylation but also validate its clinical utility as a liver-specific biomarker for HCC detection.
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PubMed
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TETRAHEDRON
·
2025
·
IF 2.2
Jiahong Chen,Yuanyuan Huang,Nan Wang,You Zi
A bstract A practical and N-selective allylation of sulfenamides using Morita-Baylis-Hillman carbonates under Lewis base catalysis is reported. It features broad substrate scope, high chemoselectivity, and tolerance to various functional groups, affording diverse N-allylated sulfenamides in good to excellent yields. Gram-scale experiments confirm its scalability, facilitating the synthesis of bioactive molecules and expanding the utility of sulfenamide chemistry.
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Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Wenhui Zhou,Boxu Dong,Shan Zhu,Fengxiang Ma,Ziqi Si,Likui Feng,Liang Zhang,Yue Zhao,Jiantao Zai,Xuefeng Qian
A Mo 2 C-bridged MoO x /N-doped carbon heterostructure (MoO x -Mo 2 C-N@C) synthesized via one-step calcination demonstrates exceptional photocatalytic activity for sulfur hexafluoride (SF 6 ) degradation, achieving a remarkable capacity of 2.12 mmol/g under UV irradiation, tenfold higher than commercial MoO 2 . The enhanced performance originates from synergistic interfacial electronic modulation: Mo 2 C channels create electron-deficient Mo sites that facilitate SF 6 adsorption and S–F bond cleavage, while N-doped carbon matrices promote charge separation and protect active centers against fluorine poisoning. This work presents an effective metal–carbon hybrid strategy for activating super-stable molecules through rational interface engineering.
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MATERIALS RESEARCH BULLETIN
·
2025
·
IF 5.7
Shengyuan Liang,Junjie Wang,Dunyan Jiang,Lijun Wang,Shikuo Li
Designing rational and lightweight magnetic-dielectric composites for efficient electromagnetic wave absorption remains a significant challenge. Herein, the FeCoNi metal-induced nitrogen-doped carbon nanotubes (FeCoNi@NCNTs) were synthesized though unique nanoconfinement strategy during carbon thermal reduction reaction. In confined environment, sufficient conditions were provided for the multidimensional growth of nanostructures. The mechanisms of carbon nanotube growth and electromagnetic wave absorption were further investigated. The FeCoNi@NCNTs exhibited a minimum reflection loss of -59.5 dB within the 2–18 GHz frequency range. Moreover, the composite achieved a minimum effective absorption bandwidth of 5.3 GHz at 2.0 mm. This work provides a new insight for preparing various magnetic-dielectric composites with rich absorption effects and broadband microwave absorption.
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JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Weiyao Geng,Feng Wei,Shichao Wang,Jun Qiao,Yaohui Lv
The insertion of ion additives into electrolyte can effectively improve the electrochemical properties of energy storage devices by redox reaction. Besides, the doping of heteroatoms increase the defect sites at the edge of carbon materials (CMs), induce the reaction of Zn 2+ with functional groups, thereby enhancing the capacity of carbon materials. Herein, the N doped carbon nanosheets with excellent surface area of 1318.2 m 2 g −1 are prepared using glycine as nitrogen sources. The synergistic effect of the introduction of nitrogen into CMs and the addition of redox ion additives into electrolyte enhances the storage performance of zinc ions, resulting in intriguing specific capacity of 211.8 mAh g −1 , superior energy output of 177.5 Wh kg −1 and outstanding cycle life with capacity decay of 0.000075 % per cycle in 1 M Zn(CF 3 SO 3 ) 2 /0.1 M ZnI 2 electrolyte. This work supplies a feasible method to enhance the zinc ion storage properties by doping of heteroatoms into CMs and introducing of ion additives into electrolyte.
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CHEMPHYSCHEM
·
2013
·Vol. 14
·期 13
·2954-2960
·
IF 3.349
Chunyang He,Dongqing Wu,Fan Zhang,Minzhao Xue,Xiaodong Zhuang,Feng Qiu,Xinliang Feng
Graphical Ruling chains: A set of n -type conjugated molecules containing a tetraazaanthracene core and different alkyl-chain arms is presented. In binary solvent mixtures, self-assembly into 2D sheet-like nanostructures takes place (see picture). By using different alkyl chains, morphology can be sensibly modified. The weak interactions arising from the heteroatoms in the conjugated backbones play a key role in the formation and stabilization of the layered structures. On the basis of our previous communication concerning a new family of thiophene-armed tetraazaanthracene molecules, we present a further intensive investigation on this class of compounds substituted with different alkyl chains and their self-assembled two-dimensional (2D) nanostructures. These tetraazaanthracene molecules with different alkyl chains were prepared in good yields using the synthetic strategy we developed. In addition to the expected typical n -type character, one compound exhibited aggregation behavior upon electrochemical reduction. Moreover, all molecules in the neutral state showed a strong tendency to aggregate in a binary solvent, as confirmed by optical spectral measurements. To investigate such self-assembly behavior, a phase-transfer method with a dichloromethane/methanol (2:3) binary solvent system was used to prepare the nanostructures. By means of atomic force microscopy, transmission electron microscopy, and X-ray diffraction, we found that the morphology of assembled 2D sheet-like structures could be adjusted by varying the alkyl chain. The weak interactions arising from the heteroatoms (N and S) in the conjugated backbones play a key role in the formation and stabilization of layered structures.
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iScience
·
2022
·
IF 6.107
Kefeng Wang,Qingzhen Yu,Wenli Mao,Yuxin Zheng,Jing Xu,Yukun Wang
Vinylboron compounds are important compounds in organic chemistry and biology. In this communication, we developed a copper(I)-catalyzed, highly regio- and stereoselective radical trans -hydroboration of ynamides with N -heterocyclic carbene (NHC)-ligated borane is reported, which leads to a series of trans -boryl enmides that can be conveniently transformed into various multi-substituted enamides. Further investigation showcased that our method is robust and scalable. The mechanism of this unique reaction is studied and discussed.
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