MACROMOLECULES
·
2022
·
IF 6.057
Yuanyuan Dou,Nan Tian,Zhenbo Ning,Ni Jiang,Zhihua Gan
Polyesteramides have attracted much attention due to their intriguing properties. However, the synthesis of di- or triblock polyesteramides based on polyamide 6 (PA6) remains challenging owing to their harsh reaction conditions. In this work, we introduced a new strategy to synthesize poly(ε-caprolactone)-block-PA6-block-poly(ε-caprolactone) (PCL-b-PA6-b-PCL) in a mild way. A series of well-designed copolymers were characterized by gel permeation chromatography, 1H, DOSY, and 13C NMR, and their crystallization and melting behavior, degradation rate, and compatibilization effect on PA6/PCL blends were found to be strongly composition dependent. Interestingly, the copolymers exhibited diverse spherulite morphologies, including curving stems and banded spherulites, which also correlated with the different relative content of PA6. Besides, PA6 nanodomains could act as physical cross-linking points to improve the tensile strength and Young’s modulus of PCL. This work fills the synthesis gap of well-defined PA6-based triblock polyesteramides, providing new materials for material modification and elucidation of some basic scientific questions.
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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DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 32
·27102-27112
·
IF 3.289
Lei Li,Beibei Lu,Qikui Fan,Lulu Wei,Jianning Wu,Jun Hou,Xuhong Guo,Zhiyong Liu
In this work, well-defined pH-responsive methoxy poly(ethylene glycol)-block-poly(ε-caprolactone)-block-poly[2-(dimethylamino)ethyl methacrylate]-g-7-propinyloxy coumarin triblock amphiphilic copolymers (mPEG-b-PCL-b-PDMAEMA-g-PC) were synthesized using a combination of atom transfer radical polymerization (ATRP), ring opening polymerization (ROP) and click chemistry. The chemical structures and compositions of these copolymers were characterized using Fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H NMR). The molecular weights of the copolymers were obtained using 1H NMR spectroscopy and gel permeation chromatography (GPC) measurements. Subsequently, the polymers could self-assemble into micelles which were investigated using dynamic light scattering (DLS), transmission electron microscopy (TEM), and fluorescence spectroscopy. The pH-responsive self-assembly behavior of these triblock copolymers in water were investigated at different pH values of 5 and 7.4 for controlled doxorubicin release, the results indicated that the release rate of DOX could be effectively controlled by altering the pH, DOX was sealed in neutral surroundings and DOX release was triggered in acidic surroundings. CCK-8 assays and confocal laser scanning microscopy (CLSM) against HeLa cells indicated that the micelles had no associated cytotoxicity, possessed good biodegradability and biocompatibility, and identified the location of the DOX in HeLa cells. The DOX-loaded micelles possessed high cytotoxicity to HeLa cells and exhibited inhibition of the proliferation of HeLa cells. Moreover, these flexible micelles with an on–off switched drug release may offer a promising pattern to deliver a wide variety of hydrophobic payloads to tumor cells for cancer therapy.
研究领域:
材料科学
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纳米技术
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药学
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生物医学工程
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DOI
高影响因子
JOURNAL OF FLUORESCENCE
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2020
·Vol. 30
·期 3
·427-435
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IF 2.093
Ruan Bo,Liu Huan-Li,Xie Lei,Ding Hui,Zhang Ya,Wu Jin,Huang Zhe,Shi Dean,Jiang Tao,Tsai Fang-Chang
Sulforhodamine B (SRB) is widely utilized for cell staining and laser field. But its application is limited by aggregation-caused quenching (ACQ). In this work, we evaluated the use of UiO-66 and UiO-67 of Zr-based metal organic frameworks (Zr-MOFs) as the host to adsorb SRB molecules due to the high stabily and good loading capacity of Zr-MOFs. The fluorescence properties of the compounds were then discussed respectively. Due to the aperture difference between UiO-66 and UiO-67, they showed distinct fluorescence properties after loading SRB. When the concentration reaches 5 ppm, fluorescence quenching begins to occur in SRB@UiO-66, while it occurs in SRB@UiO-67 at 2 ppm. The solution of quenching phenomenon could open new avenues for the extensive use of SRB.
研究领域:
材料科学
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生物医学
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产品关联
DOI
PubMed
高影响因子
Polymer Chemistry
·
2015
·Vol. 6
·期 13
·2445-2456
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IF 5.52
Minghui Xu,Junmin Qian,Aili Suo,Ting Liu,Xuefeng Liu,Hongjie Wang
To enhance the therapeutic efficacy of doxorubicin (DOX) to breast cancer cells, a multifunctional triblock copolymer, poly(ethylene glycol)-block-poly(L-glutamic acid γ-hydrazide)-block-polyethylenimine (PEG-b-PGAH-b-PEI) having a cleavable disulfide linkage between blocks, was developed as a vehicle for targeted co-delivery of DOX and P-glycoprotein (P-gp) siRNA into MCF-7/ADR cells. The PGAH blocks were used to chemically conjugate DOX molecules via hydrazone bonds, while the PEI blocks could complex siRNA through electrostatic interactions. A tumor-targeting agent, folic acid (FA), was attached to the distal ends of the PEG blocks to specifically bind to the folate receptors overexpressed in MCF-7/ADR cells. The DOX-conjugated copolymer would self-assemble in aqueous solutions into cationic nanomicelles, which could condense siRNA to form nanomicelleplexes with an average particle size of ∼194 nm and a positive zeta potential of >+10 mV. The nanomicelleplexes exhibited sustained drug release profiles, and the release rates of DOX and siRNA from the nanomicelleplexes in a reductive acidic environment (pH 5.0 + 10 mM glutathione) were much faster than those under physiological conditions (pH 7.4). FA-decorated nanomicelleplexes were more efficiently internalized by MCF-7/ADR cells via folate-receptor-mediated endocytosis and exhibited a higher cytotoxic effect on MCF-7/ADR cells in comparison with FA-undecorated nanomicelleplexes. Furthermore, the synergistic effects of DOX and P-gp siRNA in inhibiting cell proliferation and inducing apoptosis in MCF-7/ADR cells were achieved by the FA-targeted co-delivery system. The triblock copolymer itself had a low cytotoxicity. These results indicate that the triblock copolymer could serve as an ideal tumor-targeting vehicle for simultaneous delivery of drugs and siRNA in breast cancer therapy.
研究领域:
药学
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纳米技术
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癌症治疗
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药物递送系统
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生物医学工程
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Yitao Wu,Yinyan Gong,Jiaqi Liu,Zhen Zhang,Yan Xu,Hui Ren,Can Li,Lengyuan Niu
B and Y doped titanium dioxides (TiO 2 ) photocatalysts were synthesized by a sol-gel method followed by calcination . It is observed that the photodegradation efficiency of B and Y co-doped TiO 2 is twice that of undoped sample. To explore the underlining mechanism, x-ray diffraction, Raman, scanning electron microscope, x-ray photoemission, and UV–Vis diffuse reflectance spectroscopy measurements have been carried out to investigate the effect of B and Y doping on the structural, electronic, and optical properties of titania. Experimental observations revealed that in TiO 2 lattice Y 3+ ions tend to replace Ti 4+ ions while B 3+ ions occupy the interstitial sites. The incorporation of interstitial boron dopants will create oxygen vacancies ( Ov ·· ) and reduce Ti 4+ to Ti 3+ to form [ Ov ·· -Ti 3+ ] + complex, which traps the carriers and prolongs carrier lifetime. Moreover, Y 3+ ions can trap the photo-excited electrons to form Y 2+ ions, which will then react with the absorbed O 2 on TiO 2 surface to generate reactive species. In addition, all the doped samples have smaller crystallite sizes . The formation of B interstitials and Y substitutes, and increased surface-to-volume ratio are all beneficial to improve photocatalytic activity.
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 MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 4
·1-19
·
IF 2.8
Yao Bingdong,Zheng Guangwei,Luan Yina,Wang Lingxu,Xing Xuemin,Wang Yangyang,Liu Yan,He Jingxian,Zhang Fengqing
The morphology-controlled synthesis of nanostructured photocatalysts by an environmentally friendly and low-cost method provides a feasible way to realize practical applications of photocatalysts. Herein, Bi 2 WO 6 (BWO) nanophotocatalysts with mulberry shape, sheet-like, and round-cake morphologies have been successfully synthesized through a highly facile solvothermal process by simply adjusting the solvothermal temperature or utilizing selective addition of ethylene glycol as an orientation agent without using strong acids and bases and/or hazardous chemicals. The ratio of ethylene glycol and glacial acetic acid can affect the morphology and oxygen vacancy content of BWO, thereby influencing the photocatalytic performance. The photocatalytic activity of the as-prepared samples was evaluated by degradation of rhodamine B (RhB) and tetracycline under visible-light irradiation. The results indicated that all the BWO samples exhibited morphology-associated photocatalytic activity, and the sheet-like structure of BWO obtained via solvothermal treatment at 120 °C with ethylene glycol and glacial acetic acid ratio of 1:3 achieved the maximum specific surface area and possessed abundant oxygen vacancies, exhibiting outstanding photocatalytic activity for degradation of RhB and tetracycline. The degradation rate of RhB reached 100% within 20 min. To the best of our knowledge, this value is one of the most remarkable values for pristine BWO photocatalysts. Radical capture experiments demonstrated that hydroxyl radicals (·OH) play major roles compared with electrons (e − ) and holes (h + ) in the photocatalytic degradation process. A possible mechanism for the photocatalytic degradation of pollutants was proposed to better understand the reaction process. We believe that the more economical, efficient and greener methodology can provide guidance to develop highly efficient photocatalysts with favourable morphology and structure.
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
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2022
·
IF 5.876
Xiuli Shao,Siqi Wang,Youhui Zhou,Xuan Zhang,Haizhou Tian,Zheng Wang,Zhong-Yong Yuan,Huanting Wang
The ZSM-5 zeolite nanosheets are highly desired materials for catalytic reactions and membrane separation . Their synthesis depends on specially designed complex surfactants ; however, the high-cost limits their large-scale industrial production. Herein, the tailored synthesis of coffin-shaped multilamellar ZSM-5 composed of orderly stacked 2D nanosheets is carried out using cetyltrimethylammonium bromide (CTAB) as a structure-directing agent (SDA) in the presence of silicalite-1 seed sol. The morphology and b -axis thickness of nanosheets is controlled by adjusting the amount of silicalite-1 seed sol, CTAB/TEOS ratio, SiO 2 /Al 2 O 3 ratio, and synthesis time. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis indicate that the hydrophobic tail of CTAB acts as an inhibitor, effectively preventing the continuous growth along b -direction with an average thickness of 20–100 nm. This work highlights the role of silicalite-1 seed sol and CTAB in the orderly stacked sheets growth process. This crystallization strategy opens a facile and inexpensive approach for multilamellar ZSM-5 zeolite fabrication with 2D-nanosheets structures, and their practical applications in catalytic conversions of bulky molecules.
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
Nanomaterials
·
2020
·Vol. 10
·期 11
·2206
·
IF 4.324
Gaoqian Yuan,Gen Zhang,Kezhuo Li,Faliang Li,Yunbo Cao,Jiangfeng He,Zhong Huang,Quanli Jia,Shaowei Zhang,Haijun Zhang
Loading a noble metal on Bi4Ti3O12could enable the formation of the Schottky barrier at the interface between the former and the latter, which causes electrons to be trapped and inhibits the recombination of photoelectrons and photoholes. In this paper, AgPt/Bi4Ti3O12composite photocatalysts were prepared using the photoreduction method, and the effects of the type and content of noble metal on the photocatalytic performance of the catalysts were investigated. The photocatalytic degradation of rhodamine B (RhB) showed that the loading of AgPt bimetallic nanoparticles significantly improved the catalytic performance of Bi4Ti3O12. When 0.10 wt% noble metal was loaded, the degradation rate for RhB of Ag0.7Pt0.3/Bi4Ti3O12was 0.027 min−1, which was respectively about 2, 1.7 and 3.7 times as that of Ag/Bi4Ti3O12, Pt/Bi3Ti4O12and Bi4Ti3O12.The reasons may be attributed as follows: (i) the utilization of visible light was enhanced due to the surface plasmon resonance effect of Ag and Pt in the visible region; (ii) Ag nanoparticles mainly acted as electron acceptors to restrain the recombination of photogenerated electron-hole pairs under visible light irradiation; and (iii) Pt nanoparticles acted as electron cocatalysts to further suppress the recombination of photogenerated electron-hole pairs. The photocatalytic performance of Ag0.7Pt0.3/Bi4Ti3O12was superior to that of Ag/Bi4Ti3O12and Pt/Bi3Ti4O12owing to the synergistic effect between Ag and Pt nanoparticles.Keywords:photocatalytic;Rhodamine B;photoreduction;Bi4Ti3O12;AgPt/Bi4Ti3O12
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
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Yiming Liang,Fulin Wang,Rui Cai,Jianen Huang,Umar Wahid,Xinrong Wei,Zhongfu Zhao,Wei Liu,Chunqing Zhang
Owing to structure advantages, poly(styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS) has garnered significant attention in the field of anion exchange membranes (AEMs) for fuel cell applications . However, its low ionic conductivity has remained a formidable obstacle for high-performance SEBS based AEMs. Herein, an innovative approach is employed, incorporating ionic oligomeric polystyrene (OPS) into physically crosslinked SEBS based AEMs, to fabricate two series of OPS/SEBS AEMs via precise control of the molecular weight and load ratio of OPS, respectively. The variables are theoretically capable of decreasing the glass transition temperature ( T g ) of the polystyrene phase below the operating temperature of fuel cells. The results demonstrate that the lower molecular weight and the higher load quantity of OPS not only broaden the ion transport channels but also lower the energy barrier of the conducting polystyrene phase. Remarkably, the membrane (1300-CHM–OH–35) with an IEC of 2.41 mmol g −1 significantly improved the ionic conductivity to 150.9 mS cm −1 at 80 °C, despite its low total polystyrene content (45.78%), and attained a peak power density of 506.26 mW cm −2 at 1100 mA cm −2 in a H 2 /O 2 single cell operating at 70 °C. This outstanding performance underscores the promising potential of our approach in the development of high-performance SEBS AEMs for fuel cell applications.
研究领域:
材料科学
·
化学工程
·
能源技术
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产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2016
·
IF 1.272
Yongsheng Lu,Xingxing Yang,Lu Xu,Zhan Wang,Yunfeng Xu,Guangren Qian
The Fe3+/persulfate system for Rhodamine B (RhB) oxidative degradation has been investigated. The catalytic mechanism in the Fe3+/persulfate system was proposed as follows: Fe3+ was restored to Fe2+ by the generated intermediate products during the degradation process. The influence parameters were examined in batch experiments, including Fe3+ and persulfate concentration and initial pH. The results indicated that the Fe3+/persulfate system exhibited good performance for RhB degradation and followed first-order kinetics. 95.91% of the RhB was removed within 30 min under the following conditions: [Fe3+]0 = 1 mM, [persulfate]0 = 1 mM and pH 3.0. The RhB degradation efficiencies increased as the Fe3+ and persulfate concentrations increased. In addition, the RhB degradation was inhibited in the presence of inorganic anions, which was primarily due to a complex reaction between Fe3+ and various anions except for .
研究领域:
环境科学
·
化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
He Ma,Dashuai Li,Yingying Li,Yuanyuan Li,Changhua Wang,Xintong Zhang
While photocatalytic technology has been recognized as an effective means for removing low-concentration NOx in ambient atmosphere, it still faces the challenge of the deep oxidation in high efficiency. In many cases, the release of more toxic NO 2 byproduct appeared to be inevitable during the photocatalytic oxidation of NO. Herein we report that the atomically dispersed MnO x cocatalyst on TiO 2 (B) microspheres could significantly enhance the deep oxidation of NOx under mild photocatalytic conditions (1 mW/cm 2 UV-A light, 1 L/min flow rate). At an initial NO concentration of 0.35 ppm, ca. 67.15% of NO is oxidized on the MT-0.5 sample, which is 2.76 times higher than the pristine TiO 2 (B) sample. More importantly, the release of NO 2 is suppressed by 2.11 times. Comprehensive spectral analyses suggest that atomically dispersed MnO x effectively promotes the charge separation of photogenerated carriers in TiO 2 (B), even better than MnO x nanoparticles-loaded TiO 2 (B). EPR and in-situ FTIR analyses illustrate that atomically dispersed MnO x -loaded TiO 2 (B) sample exhibits excellent low concentration NOx abatement performance, thus providing a rational mechanism for the NO deep oxidation pathway. This study not only provides a unique approach for preparing non-noble metal atomically dispersed co-catalysts, but also affords an effective means for efficient photocatalytic NO degradation.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2015
·Vol. 33
·期 3
·456-464
·
IF 1.835
Xiao Jun-jie,Li Xiu-bing,Wang Xi,Yi Chun-wang,Su Sheng-pei
The effect of temperature-responsive solution behavior of PNIPAM- b -PPEOMA- b -PNIPAM on its inclusion complexation with α -cyclodextrin was studied. The triblock polymer was prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization and formed inclusion complexes (ICs) after selective threading of the PEO segment of the triblock polymer through the cavities of α -CD units. For comparison, PPEOMA homopolymer was prepared and the inclusion complexation with α -CD was also studied. The ICs were prepared with α -CD when the polymer was in different conformations by changing the temperature, and the formed ICs were characterized by XRD, 1 H-NMR, TGA and DSC. The solutions of the ICs show temperature-responsive clear/turbid transition or fluidic emulsion/gel transition depending on the concentration of the α -CD added, and the stoichiometry determined by 1 H-NMR and TGA indicates that the stoichiometry of EO to α -CD of the resulted ICs increases with increasing of temperature.
研究领域:
高分子科学
·
材料化学
·
物理化学
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产品关联
DOI
高影响因子