JOURNAL OF MATERIALS SCIENCE
·
2025
·
IF 3.9
Qi Lun,Tu Dan,Shi Yu,Liu Jingjing,Zhao Xinyuan,Xu Jianhua,Yang Yajie,Yang Wenyao
Zeolitic imidazolate frameworks (ZIFs) have greatly attracted attention in supercapacitors research due to their porosity and structural controllability. In this paper, a series of Co–nitrogen carbon (Co–NCs) were obtained via a facile one-step calcination process using 3D star-shaped Co–ZIF as a precursor. The energy storage mechanism is analyzed and it is concluded that Co–NCs show excellent capacitance and cycling stability, attributed to its star-shaped porous morphology and high pseudocapacitance contribution. The optimized Co–NCs/550 exhibits a specific capacity of 825 F g −1 at a current density of 0.1 A g −1 , and a highly stable cycling performance over 5000 cycles at a current density of 2 A g −1 . This work provides a practical strategy for designing stable electrode for high-performance supercapacitors.
研究领域:
材料科学
·
电化学
·
纳米技术
·
储能
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产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2024
·
IF 3.2
Yunchao Ma,Shengnan Qi,Yuxin Yao,Chuanxue You,Chunbo Liu,Baixiang Ren
Covalent organic frameworks (COFs) are widely used for gaseous radioiodine capture through distinctive properties. Herein, 2D fluorinated imine COF (JLNU-316) was designed and constructed in this study. JLNU-316 exhibited large BET surface area of 596.25 mg 2 /g and pore size (2.74 and 3.78 nm), excellent thermal and chemical stability. The adsorption of iodine by JLNU-316 reached 4.08 g/g, which exceeded most of the current fluorine-containing porous iodine adsorption materials. Furthermore, the iodine adsorption capacity remains at 99 % after seven days of exposure to air conditions, and JLNU-316 maintains stable performance following ten cycles. The introduction of heteroatoms enhanced the stability of JLNU-316 and enriched the adsorption sites, thereby increasing the iodine adsorption capacity. This study guides for the design and preparation of novel iodine adsorbents.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF COORDINATION CHEMISTRY
·
2021
·
IF 1.751
Na Zhang,Yuying Li,Liduo Chen,Cuiqin Li,Guoliang Mao,Jun Wang
A series of star iminopyridine ligands, containing different groups (H, CH3, Br) in the pyridine ring, have been synthesized and characterized by FT-IR, 1H NMR, and UV-vis. The corresponding nickel(II) complexes have been prepared in good yields. The nature of the Ni complexes has been established by FT-IR, UV-vis, ESI-MS, and ICP. Upon activation with methylaluminoxane (MAO), the nickel complexes were able to oligomerize ethylene to produce C4–C18 fractions at activity of up to 105 g (mol Ni h)−1. The influence of substituent, catalyst structure, solvent, co-catalyst, and reaction conditions on the catalytic activity and product selectivity was investigated. The results showed that substitution on the pyridine ring had large influence on the catalytic activity and product selectivity. The catalytic activity increased at first and then decreased with the increase of reaction temperature and Al/Ni molar ratio. However, the catalytic activity continuously increased with increasing reaction pressure. When toluene was used as solvent and MAO was used as co-catalyst, catalytic activity of 4.39 × 105 g (mol Ni h)−1 and 31.93% selectivity of higher carbon olefins (C8–C18) were obtained at 10 °C, Al/Ni molar ratio 500, and the reaction pressure 1.0 MPa.
研究领域:
有机化学
·
催化化学
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产品关联
DOI
高影响因子
Polymers
·
2019
·Vol. 11
·期 10
·1574
·
IF 3.164
Yuanjie Wang,Xinzhi Liu,Liying Liu,Hui Niu
In this work, a series of isotactic-polypropylene/atactic-polystyrene (iPP/aPS) miktoarm star copolymers, PxSy, was synthesized via an arm-first approach. Varied star macromolecule architectures were fabricated by designing the arm length and the arm numbers (x and y). These miktoarm stars were able to form micelles in selective solvent (N,N′-dimethylformamide (DMF)), in which the insolubleiPP arms formed the core and the solubleaPS arms formed the shell. The miktoarm polymers aggregated to micro-nanoscale binary structures (MNBSes) in the casting process, and their morphologies, including the MNBS shape and size, were greatly influenced by the PxSyarchitectures. The MNBSes endowed the material surface with superhydrophobic performance with a water contact angle of 157.0° and a sliding angle of 1.5°.Keywords:miktoarm star copolymer;isotactic-polypropylene;atactic-polystyrene;aggregation morphology
研究领域:
高分子化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
POLYMER BULLETIN
·
2015
·Vol. 72
·期 11
·2949-2965
·
IF 1.438
Ren Qiang,Xiang Yanli,Huang Chunyan,Li Jian,Wang Chengyi
A novel epoxy resin toughener based on star-shaped copolymer of butyl acrylate (BA) and glycidyl methacrylate (GMA) [poly (BA- co -GMA)] with low viscosity was developed. The star polymers were synthesized by initiators for continuous activator regeneration atom transfer radical polymerization (ICAR ATRP) using tri, tetra and hexa-functional initiators. The branching parameters of star poly (BA- co -GMA) were characterized by gel permeation chromatography with a laser light scattering-viscometry triple detection system. Copolymer composition and glass transition temperatures of the copolymers were analyzed by proton nuclear magnetic resonance ( 1 H-NMR) and differential scanning calorimetry (DSC), respectively. The results showed that the branching ratio decreased as the number of arms increased. The epoxide groups of the GMA units were kept intact during ICAR ATRP. Rheological, mechanical tests and dynamic mechanical analysis revealed that star poly (BA- co -GMA)/diglycidyl ether of bisphenol A (DGEBA) epoxy resin formulation exhibited better processability, higher impact resistance and thermal resistance than those of linear poly (BA- co -GMA)/DGEBA epoxy resin formulation.
研究领域:
高分子科学
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材料科学
·
化学工程
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产品关联
DOI
高影响因子
ENVIRONMENTAL TOXICOLOGY
·
2023
·
IF 4.5
Shuang Wang,Xueyan Gu,Jianhua Ma,Zhangyu Gu,Rui Zhang,Ruifen Li,Jun Bai,Peng Li,Linyu Wei,Yixing Ye,Yan Wang,Li Zhang,Li Su,Changhao Liang
The present study was designed to investigate the role of miR-708-5p/p38 mitogen-activated protein kinase (MAPK) pathway during the mechanism of selenium nanoparticles (Nano-Se) against nickel (Ni)-induced testosterone synthesis disorder in rat Leydig cells. We conducted all procedures based on in vitro culture of rat primary Leydig cells. After treating Leydig cells with Nano-Se and NiSO 4 alone or in combination for 24 h, we determined the cell viability, reactive oxygen species (ROS) levels, testosterone production, and the protein expression of key enzymes involved in testosterone biosynthesis: steroidogenic acute regulatory (StAR) and cytochrome P450 cholesterol side chain cleavage enzyme (CYP11A1). The results indicated that Nano-Se antagonized cytotoxicity and eliminated ROS generation induced by NiSO 4 , suppressed p38 MAPK protein phosphorylation and reduced miR-708-5p expression. Importantly, we found that Nano-Se upregulated the expression of testosterone synthase and increased testosterone production in Leydig cells. Furthermore, we investigated the effects of p38 MAPK and miR-708-5p using their specific inhibitor during Nano-Se against Ni-induced testosterone synthesis disorder. The results showed that Ni-inhibited testosterone secretion was alleviated by Nano-Se co-treatment with p38 MAPK specific inhibitor SB203580 and miR-708-5p inhibitor, respectively. In conclusion, these findings suggested Nano-Se could inhibit miR-708-5p/p38 MAPK pathway, and up-regulate the key enzymes protein expression for testosterone synthesis, thereby antagonizing Ni-induced disorder of testosterone synthesis in Leydig cells.
研究领域:
分子生物学
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内分泌学
·
毒理学
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DOI
PubMed
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 4
Yuan Chao-Yang,Shi Lei,Ji Shang-Chao,Chen Hai-Long,Tong Xiao,Hao Zi-Ying,Pan Xiao-Da,Yin Xian-Ze,Zheng Long
Airless tires are essential for enhancing the safety, reliability, and convenience of maintenance of electric bicycles. Polyurethane (PU) is considered a promising candidate for such applications owing to its versatile properties. However, their use is limited by insufficient heat resistance and excessive dynamic heat generation under cyclic loading. In this study, star-shaped trifunctional polypropylene glycerol (PPG3) was incorporated into conventional poly(tetramethylene glycol) (PTMG) and 4,4′-methylenediphenyl diisocyanate (MDI)-based systems to construct microporous star-shaped casting polyurethanes (SCPU), with water serving as a green foaming agent. Unlike conventional small-molecule trifunctional crosslinkers that create junctions within hard segment domains, PPG3 introduces long flexible arms between the hard segments, anchoring the crosslinking points at its molecular core. The large steric hindrance of PPG3 effectively suppresses soft segment crystallization and lowers the degree of microphase separation, whereas the crosslinked network restricts chain mobility, thereby reducing dynamic heat generation. These structural features also enhance the heat resistance, yielding a softening temperature of 183 °C, which is 30.9% higher than that of polyurethane without PPG3. When applied to airless tires by casting SCPU into rubber treads, the fabricated hybrid airless tires achieved a rolling distance of over 3000 km under a load of 65 kg at 25 km/h without structural failure, satisfying practical performance requirements. This strategy offers a simple, solvent-free, and environmentally friendly process, underscoring the potential of SCPU for scalable production of high-performance airless tires.
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2013
·Vol. 20
·期 6
·1-10
·
IF 2.019
Yang Jiaojiao,Cao Shuqin,Xin Jianyu,Chen Xingyu,Wu Wei,Li Jianshu
Layer-by-layer (LbL) systems constructed via electrostatic attraction or other forces can be used as templates in biomimetic mineralization. In this work, 21-arm star poly(acrylic acid) (star-PAA) and 21-arm star poly[2-(dimethylamino)ethyl methacrylate] (star-PDMAEMA) were successfully synthesized from a cyclodextrin core via atom transfer radical polymerization (ATRP). The star polymers were used to construct three kinds of LbL systems: negatively charged star-PAA with positively charged chitosan (CHI) as a model of unconfined space for mineralization, and positively charged star-PDMAEMA with negatively charged poly(styrene sulfonic acid) sodium salt (PSS), which had acid-etched holes or constructed within a porous polycarbonate filters, as two different models of confined space for mineralization. Different crystal forms of calcium carbonate were obtained using the three systems, so these LbL systems assembled from star polymers could be new tools for developing functional materials and investigating fundamental aspects of the mineralization process.
研究领域:
材料科学
·
仿生学
·
化学工程
✓ 已验证
DOI
高影响因子
POLYMER
·
2017
·
IF 3.684
Pengcheng Zhang,Zhenghe Zhang,Xiaoze Jiang,Leilei Rui,Yun Gao,Weian Zhang
A biotin-functionalized amphiphilic star-shaped block copolymer , POSS-(PCL- b -PDMAEMA) 8 -biotin, with an inorganic POSS nucleus, a hydrophobic poly( ɛ -caprolactone) (PCL) middle layer, a hydrophilic poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) outer corona was synthesized for the targeting delivery and pH-responsive release of hydrophobic pheophorbide A (PPa) photosensitizers . In aqueous solution, this amphiphilic copolymer was able to form unimolecular micelles as determined by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The biotin-functionalized unimolecular micelles were responsive to pH and further utilized in encapsulation and release of PPa for photodynamic therapy (PDT). The PPa release from PPa-loaded unimolecular micelles could be enhanced at acidic condition. Additionally, confocal laser scanning microscopy (CLSM) and flow cytometry results revealed that PPa-loaded tumor-targeted unimolecular micelles could boost the internalization rate in HeLa cells effectively. Moreover, PPa-loaded unimolecular micelles showed low dark toxicity and high PDT efficacy towards HeLa cells according to the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Thus, PPa-loaded POSS-(PCL- b -PDMAEMA) 8 -biotin would have presented the potential application in PDT.
研究领域:
材料科学与工程
·
生物医药
·
纳米医学
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DOI
高影响因子
POLYMER
·
2021
·
IF 4.43
Liang Xiang,Min Qiu,Minjing Shang,Yuanhai Su
With the RAFT arm-first method, butyl acrylate and 4-acryloylmorpholine were used as monomers to form linear arms, which subsequently reacted with the cross-linker 1,6-hexanediol diacrylate to form star-shaped macromolecules in cascade microreactor systems. After studying polymerization kinetics in each step, homoarm and miktoarm star products with various arm compositions were steadily prepared by optimizing the reaction flowsheet and adjusting the reactant formula. Such continuous-flow processing avoided tedious intermediate purification procedures and prepared polymer products with considerable star yield (>70%), molecular weights ( M w,LS > 100 kg/mol) and arm numbers (>30). Multiple emulsions (including two types, i.e., oil-in-water and water-in-oil) were formed utilizing star products with different amphiphilic architectures as emulsifiers . This study demonstrated that in this continuous-flow mode, through regulating the residence time and flow rate ratio in each step, the arm and core structures of star polymers were tailored to possess remarkable functional applications.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2015
·Vol. 293
·期 8
·2291-2300
·
IF 1.865
Zhou Qing-Han,Lin Juan,Li Li-Dong,Shang Le
Biodegradable micelles based on disulfide-linked monomethoxy poly(ethylene glycol)- b -poly(methyl methacrylate) 2 (mPEG-SS-PMMA 2 ) miktoarm star block copolymers were synthesized through atom transfer radical polymerization procedure and applied to solubilization and delivery of methotrexate (MTX). The synthesized miktoarm star block copolymers were characterized by 1 H nuclear magnetic resonance, Fourier transform infrared spectra, and gel permeation chromatography. The block copolymers were able to self-assemble into spherical micelles in water with an average diameter up to 130 nm by transmission electron microscopy observation and dynamic light scattering measurements and have a critical micelle concentration of 0.91 mg/L. When MTX was incorporated into obtained micelles, high drug loading capacity was found attributed to the designed miktoarm star-shaped nanostructure. Interestingly, in presence of dithiothreitol, the micelles could be degraded into polymer chains by cleavage of the disulfide linkages. The in vitro release studies revealed that these micelles released over 95 % of MTX within 48 h under a reductive environment analogous to that of the cell comparing to minimal drug release (<22 %) under nonreductive conditions. Cell cytoxicity experiments showed that the obtained micelles exhibited nontoxic, and the drug-loaded micelles exhibited high anticancer efficacy and better biocompatibility as compared to free MTX. All of these results showed that mPEG-SS-PMMA 2 micelles are promising carriers for delivery of hydrophobic antitumor drugs.
研究领域:
药学
·
高分子科学
·
纳米技术
·
药物传递
·
生物化学
·
材料科学
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2017
·
IF 3.531
Haohui Huo,Xiaoyan Ma,YeQing Dong,Fengjin Qu
A novel light- and temperature-responsive amphiphilic ABC miktoarm star terpolymer consisting of hydrophilic poly(ethylene glycol) (PEG), light-responsive poly(2-nitrobenzyl methacrylate) (PNBM), and temperature-responsive poly(N-isopropylacrylamide) (PNIPAM) arms, PEG(- b -PNBM)- b -PNIPAM, was synthesized via a combination of atom transfer radical polymerization (ATRP) and click reaction. In aqueous solution, the obtained miktoarm star terpolymer self-assembled into spherical micelles with PNBM cores and hybrid PEG/PNIPAM coronas. When heating above the phase transition temperature of PNIPAM, larger aggregates with mixed PNBM/PNIPAM cores and PEG coronas were formed. Upon UV light irradiation, the initial micelles were disrupted and reassembled into some large micelle complexes. Fluorescence emission measurements showed that Nile red encapsulated in the polymeric micelles could be released by stimuli of UV light or temperature change. More interestingly, the UV triggered release could be strengthened in basic conditions but weakened in acidic conditions. The prepared light- and temperature-responsive polymeric micelles may have great potential in applications such as nanocarriers and biotechnology for controlled drug and bioagent delivery.
研究领域:
材料科学
·
生物医学工程
·
纳米技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）