JOURNAL OF APPLIED POLYMER SCIENCE
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2016
·Vol. 134
·期 1
·
IF 1.866
Shaojie Liu,Huali Wang,Xiaomeng Chu
2,2,6,6-Tetramethylpiperidinyloxyl (TEMPO)-containing polymer brushes were grafted onto crosslinked polystyrene microspheres via surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) of 2,2,6,6-tetramethyl-4-piperidyl methacrylate, followed by an oxidation process with 3-chloroperoxybenzoic acid as oxidant. The synthesized nitroxide polymer brushes included homopolymer brushes, block copolymer brushes, and random copolymer brushes with various TEMPO contents and molecular weights. They were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, nuclear magnetic resonance spectroscopy, and gel permeation chromatography. These nitroxide brushes bearing high TEMPO contents were used as recoverable catalysts for the hypochlorite and aerobic oxidation of primary alcohols to aldehydes. The effects of polymer brush structure on the catalytic properties were studied and discussed. The results showed that these nitroxide polymer brushes had excellent catalytic properties and good recycling performances. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 44365.
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Polymer Chemistry
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2016
·Vol. 7
·期 41
·6297-6308
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IF 5.687
Xin Wang,Jiaqi Liu,Songquan Xu,Jiaxi Xu,Xianfu Pan,Jingjing Liu,Saide Cui,Zhenjiang Li,Kai Guo
Catalytic ring-opening polymerization (ROP) of the three major types of cyclic monomers, lactides, lactones, and carbonates, showed match and mismatch between the monomer and the catalyst. Therefore, one organocatalyst that works for all of the three in ROPs by a controlled/living nature is rare in ROPs. Herein, we proposed a traceless switch organocatalysis (TSOC) strategy and demonstrated it by switching from a Brønsted acid cationic to base/conjugate-acid bifunctional mechanisms in ROPs. Ring-opening copolymerization (ROCOP) of different types of monomers of lactones to lactides, and carbonates to lactides by organocatalysis was realized through an acid plus a base, i.e. “one plus one”, approach in one pot. The TSOC was exemplified by a methanesulfonic acid (MSA)/8-diazabicyclo[5.4.0]undec-7-ene (DBU) pair, and by diphenylphosphate (DPP)/DBU pair catalysis. DPP catalyzed cationic ROPs of δ-valerolactone (VL) and trimethylene carbonate (TMC); orthogonally, “DPP plus DBU” switched it into DPP/2DBU catalyzed bifunctional ROPs of L-lactide (LA), producing sequences of PVL-b-PLA, and PVL-b-PTMC-b-PLA. Alternatively, MSA catalyzed cationic ROPs of ε-caprolactone (CL) and TMC; switching it into MSA/2DBU catalyzed ROPs afforded block copolymers of PCL-b-PLA and PCL-b-PTMC-b-PLA. All the di- and triblock copolymers were characterized using 1H NMR, 13C NMR, and SEC; each showed its exact sequence length, predicted molecular weight, and narrow dispersity. An ROCOP of the three major types of carbonyl-containing cyclic monomers using a single organocatalysis platform, in one pot, via a traceless switch, and through multi-feeding of the monomers, to sequence controlled multiblock copolymers was fulfilled.
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ChemCatChem
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2016
·Vol. 8
·期 23
·3680-3687
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IF 4.724
Xinbo Dong,Xi Zhang,Panfeng Wu,Yanjie Zhang,Bin Liu,Huaiming Hu,Ganglin Xue
Graphical Animal magnetism : A magnetically recoverable catalyst is fabricated by immobilizing divanadium-substituted Keggin phosphotungstate on mesoporous-silica-coated Fe 3 O 4 core–shell nanoparticles by a facile procedure. This material presents a high catalytic activity for the selective oxidation of alcohols. A new magnetically recyclable catalyst (Fe 3 O 4 @mSiO 2 /NH-PV 2 W) was fabricated by immobilizing divanadium-substituted Keggin phosphotungstic acid H 5 PV 2 W 10 O 40 on mesoporous-silica-coated Fe 3 O 4 core–shell nanoparticles by a facile procedure. The magnetic core–shell nanoparticles were prepared by coating a thin mesoporous silica shell directly on pristine magnetic Fe 3 O 4 and functionalized with amino radicals simultaneously. Then the active H 5 PV 2 W 10 O 40 was immobilized on the mesoporous silica shell of the Fe 3 O 4 core–shell nanoparticles. The obtained catalyst was characterized by using SEM, TEM, IR spectroscopy, XRD, N 2 sorption–desorption, and magnetometry. The catalytic properties were evaluated for a series of alcohols that were oxidized selectively to the corresponding aldehydes or ketones using hydrogen peroxide as the oxidant. The results show that H 5 PV 2 W 10 O 40 -loaded mesoporous silica-coated Fe 3 O 4 catalyst presents high catalytic activities with 98 % conversion of benzyl alcohol and 99 % selectivity to benzaldehyde. After the reaction, the catalyst could be separated easily with an external magnetic field, and the recovered catalyst could be reused at least five times without any loss of catalytic activity.
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Micromachines
·
2017
·Vol. 8
·期 2
·55
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IF 1.833
Peng Zhou,Wangnan Li,Tianhui Li,Tongle Bu,Xueping Liu,Jing Li,Jiang He,Rui Chen,Kunpeng Li,Juan Zhao,Fuzhi Huang
Flexible electronics have attracted great interest in applications for the wearable devices. Flexible solar cells can be integrated into the flexible electronics as the power source for the wearable devices. In this work, an ultrasonic spray-coating method was employed to deposit TiO2nanoparticles on polymer substrates for the fabrication of flexible perovskite solar cells (PSCs). Pre-synthesized TiO2nanoparticles were first dispersed in ethanol to prepare the precursor solutions with different concentrations (0.5 mg/mL, 1.0 mg/mL, 2.0 mg/mL) and then sprayed onto the conductive substrates to produce compact TiO2films with different thicknesses (from 30 nm to 150 nm). The effect of the different drying processes on the quality of the compact TiO2film was studied. In order to further improve the film quality, titanium diisopropoxidebis(acetylacetonate) (TAA) was added into the TiO2-ethanol solution at a mole ratio of 1.0 mol % with respect to the TiO2content. The final prepared PSC devices showed a power conversion efficiency (PCE) of 14.32% based on the indium doped tin oxide coated glass (ITO-glass) substrate and 10.87% on the indium doped tin oxide coated polyethylene naphthalate (ITO-PEN) flexible substrate.Keywords:ultrasonic spray;titanium oxide;flexible perovskite solar cells;low temperature;large area
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APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
·
IF 9.446
Xueqing Xu,Ruxue Liu,Yuhan Cui,Xixi Liang,Cheng Lei,Shuangyan Meng,Yali Ma,Ziqiang Lei,Zhiwang Yang
Metal-organic frameworks (MOFs), a new class of porous crystalline materials, have attracted great interest as fascinating applications for eco-friendly photocatalysts. In this study, new hybrid MOFs, iron doped zirconium based metal-organic frameworks, FeUiO-66, were successfully synthesized by hydrothermal method firstly. Then the PANI/FeUiO-66 nanohybrids were fabricated through annealing process. The photocatalytic performances of the obtained PANI/FeUiO-66 nanohybrids were evaluated by selectively oxidation of various alcohol substrates using molecular oxygen as a benign oxidant. Boosting by synergistically multi-doped effect, the catalytic activity of the novel PANI/FeUiO-66 is remarkably higher than that of bare UiO-66 under visible light irradiation at ambient temperature. Further analyses revealed that the enhancement of photocatalytic activity originated from the two aspects. On one hand, when the Fe doped into the framework, valence fluctuation of Fe 2+ /Fe 3+ could reduce the recombination rate of photoexcited carriers. On the other hand, based on energy band matching between FeUiO-66 and PANI, the easily formed heterostructures from PANI and FeUiO-66 can efficiently enhance the separation of photogenerated carriers. Furthermore, by virtue of unique advantage of the position of the CB and VB of FeUiO-66, alcohols could be selectively oxidized by the O 2 − and h + . Remarkably, it is expected that the MOF-conductive conjugated polymers nanohybrids could be used as efficient visible light driven photocatalysts for organic transformation with high selectivity under eco-friendly conditions.
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INTERNATIONAL JOURNAL OF PHARMACEUTICS
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2016
·
IF 3.994
Tao Liu,Qianxia Huang
Well-defined amphiphilic tumor-targeting brush-type copolymers, poly(oligo(ethylene glycol) monomethyl ether methacrylate- co -G3-C12)- g -poly(ε-caprolactone) (P(OEGMA- co -G3-C12)- g - PCL), were synthesized by the combination of ring-opening polymerization (ROP), reversible addition-fragmentation transfer (RAFT) polymerization and polymer post-functionalization, in which G3-C12 was castration-resistant prostate cancer (CRPC) targeting peptide. The obtained polymers were then employed for the targeted treatment of CRPC by delivering a hydrophobic anticancer drug (bufalin, BUF). Polymerizable monomer, 3-((2-(methacryloyloxy)ethyl)thio)propanoic acid (BSMA) and PCL-based macromolecular monomer (PCLMA) were synthesized at first. RAFT polymerization of OEGMA, BSMA, and PCLMA afforded amphiphilic brush-type copolymers, P(OEGMA- co -BSMA)- g -PCL. Post-functionalization of the obtained polymers with G3-C12 led to the formation of the final amphiphilic targeting brush-type copolymers, P(OEGMA- co -G3-C12)- g - PCL. In aqueous media, P(OEGMA- co -G3-C12)- g -PCL self-assembles into micelles with a hydrodynamic diameter ( D h ) of ∼66.1 ± 0.44 nm. It was demonstrated that the obtained micellar nanoparticles exhibited good biocompatibility and biodegradability. Besides, BUF-loaded micellar nanoparticles assembled from P(OEGMA- co -G3-C12)- g -PCL, BUF-NP-(G3-C12), showed a controlled drug release in vitro and improved anticancer efficacy both in vitro and in vivo.
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PubMed
高影响因子
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
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2016
·
IF 0.62
Jian Sun,Tao Liu,Jianhua Xu
Alfa-hederin (Hed) is regarded as a promising drug in cancer therapy especially in drug-resistant cancers. However, its reduced anticancer activity caused by protein absorption limits its wide clinical applications. The purpose of this study was to develop diblock copolymer-based micelles as an integrated platform for targeted delivery of Hed to overcome its intrinsic drawbacks. Amphiphilic diblock copolymers, poly(epsilon-caprolactone)- b -poly(oligo(ethylene glycol) monomethyl ether methacrylate- co -RGD) (PCL- b -P(OEGMA- co -RGD)) consisting of hydrophobic PCL, hydrophilic POEGMA and targeting peptide (RGD) were fabricated via the combination of ring-opening polymerization (ROP), atom transfer radical polymerization (ATRP), and polymer post-functionalization. Hed-containing targeting micellar nanoparticles , Hed-NP-RGD, were obtained via the co-micellization of PCL- b -P(OEGMA- co -RGD) and Hed, showing hydrodynamic diameter 108 ± 1 nm and zeta potential −4.10 ± 0.15 mV. In vitro experiments demonstrated that Hed-NP-RGD possessed superior anti-proliferative and cellular apoptosis in comparison with that of free Hed possibly due to the assumption that the presence of polymeric micelles protected Hed molecules from absorption by proteins and tumor-targeting effect.
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MACROMOLECULAR BIOSCIENCE
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2016
·Vol. 17
·期 4
·1600295
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IF 3.68
Caiyan Zhao,Leihou Shao,Jianqing Lu,Chenying Zhao,Yujie Wei,Junxing Liu,Mingjun Li,Yan Wu
Stimuli-responsive nanocarriers with the ability to respond to tumorous heterogeneity have been extensively developed for drug delivery. However, the premature release during blood circulation and insufficient intracellular drug release are still a significant issue. Herein, three disulfide bonds are introduced into the amphiphilic poly(ethylene glycol)-polycaprolactone copolymer blocks to form triple-sensitive cleavable polymeric nanocarrier (tri-PESC NPs) to improve its sensitivity to narrow glutathione (GSH) concentration. The tri-PESC NPs keep intact during blood circulation due to the limited cleaving of triple-disulfide bonds, whereas the loaded drug is efficiently released at tumor cells with the increased concentration of GSH. In vitro studies of doxorubicin-loaded tri-PESC NPs show that the nanocarriers achieve sufficient drug release in cancerous cells and inhibit the tumor cells growth, though they only bring minimum damage to normal cells. Therefore, the tri-PESC NPs with triple-sensitive cleavable bonds hold great promise to improve the therapeutic index in cancer therapy.
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PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Yumei Zhu,Jinlv Wei,Jia Wu,Rong Chen,Panagiotis Tsiakaras,Shibin Yin
The development of catalysts with suitable adsorption behavior for the reaction molecules and the elucidation of their internal structure-adsorption-catalytic activity relationships are crucial for the electrooxidation of 5-hydroxymethylfurfural (HMF). In this work, NiO-CuO heterostructures with a spontaneous built-in electric field (BEF) are specifically designed and used to regulate the OH − adsorption site for freeing up the active site of HMF for the HMF oxidation reaction (HMFOR). The mechanism driving electron pumping/accumulation of the BEF is examined by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). Electrochemical data and theoretical calculations show that BEF modulates the adsorption energy and adsorption site of substrate molecules, thereby enhancing the performance of HMFOR and hydrogen evolution reaction (HER). Notably, the NiO-CuO electrode demonstrates high 2,5-Furandicarboxylic acid (FDCA) selectivity (99.76 %) and generation rate (13.79 mmol gcat −1 h −1 ). It only requires 1.33 V to obtain a current density of 10 mA cm −2 for HMFOR-coupled H 2 evolution. This research introduces a novel approach by regulating the adsorption of reactive molecules for HMFOR-assisted H 2 evolution.
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FOOD RESEARCH INTERNATIONAL
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2024
·
IF 7
Jie-Qiong Wang,Ying Gao,Zhi-Hui Feng,Si-Han Deng,Jian-Xin Chen,Fang Wang,Yi-Fan Li,Ying-Bin Zhang,Jun-Feng Yin,Liang Zeng,Wei-Biao Zhou,Yong-Quan Xu
The deterioration of aroma quality in tea beverages during the shelf life is a significant issue. In this study, sensomics techniques were employed to identify the characteristic factor contributing to aroma degradation in green tea infusion. Samples A (no/faint retort odor) and B (high intensity retort odor) were selected based on their retort-like odor intensity after heat treatment simulating shelf-life conditions. The key odorants were identified through a combination of chemometrics analysis, comparative aromatic extract dilution analysis (cAEDA), detection frequency analysis (DFA), and odor-specific magnitude estimation (OSME). Subsequently, eight odorants, including linalool (892.451 μg/L), ( E )- β -damascenone (5.105 μg/L), phenylacetaldehyde (27.720 μg/L), nonanal (2201.439 μg/L), α -terpineol (7.166 μg/L), geraniol (0.499 μg/L), theaspirane (0.044 μg/L), and 2-hydroxy-5-methylacetophenone (2.973 μg/L), were identified as the key substances contributing to the retort-like odor in sample B. Aroma recombination and omission test further demonstrated that elevated concentrations of nonanal, geraniol, phenylacetaldehyde, and theaspirane might be the primary reasons for the retort odor observed in samples.
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高影响因子
Journal of Environmental Chemical Engineering
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2024
·
IF 7.4
Jing Li,Xiang-Dong Xu,Jian Zhang,Xin-Yi Sui,Jian-Bo Qu
Macroporous polystyrene microspheres have been extensively used as an efficient carrier for lipase immobilization owing to the hydrophobic surface , excellent mechanical strength and chemical stability, easy to recycle and low cost. However, conventional polystyrene microspheres usually have a pore size of less than 100 nm and an extremely hydrophobic surface lacking functional groups, which bring a series of problems such as low enzyme loading, activity recovery, reusability, serious leakage, and high substrate diffusion limitation. In this work, a novel generation of gigaporous polystyrene microspheres with moderately hydrophilic surfaces was specifically designed as an enzymatic carrier. The microspheres were featured with micropores (∼ 9 nm), mesopores (∼ 54 nm), and gigapores (∼ 948 nm), ensuring native enzyme structure preservation and high loading capacity. After epoxy activation, the lipase PS from Burkholderia cepacia (PPL) was site-specifically immobilized onto the microspheres. The resultant immobilized PPL exhibited 95 % activity recovery at a maximum loading of 115.3 mg/g. Also, the immobilized PPL surpassed free PPL in pH and temperature tolerances, temperature and storage stabilities, and achieved a 91.6 % yield in benzyl cinnamate biosynthesis. Besides, excellent reusability of the immobilized PPL was demonstrated with an 80.1 % yield after 10 cycles. Overall, these gigaporous microspheres show great potential for the highly efficient immobilization of lipase and enhanced benzyl cinnamate production.
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JOURNAL OF STORED PRODUCTS RESEARCH
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2024
·
IF 2.7
Yan Yan Lin,Min Xing Zhang,Miao Sun,Lu Sheng Wan,You Zhou,Jing Sheng Chen
Tribolium castaneum is recognized as one of the most significant global pests affecting stored grains. Due to their general safety, essential oil (EO)-based biopesticides have garnered increasing interest worldwide. To provide a more rapid and objective method for the identification of individual components with potential fumigants from EOs, a GC-MS-based metabolomics strategy was applied in this study. Five EOs— Eucalyptus globulus , Dendranthema indicum , Cinnamomum cassia , Pinus massoniana , and Cinnamomum camphora —demonstrated remarkable toxicity, achieving corrected mortality rates exceeding 90% against Tribolium castaneum . A total of 41 potential fumigants were screened, with 21 of these identified potential fumigants corroborated by existing literature or preliminarily bioassay experiments. Key components included (−)-myrtenol, β-pinene, p -cymene, γ-terpinene, sabinene, β-myrcene, β-ocimene, and α-terpinene. These findings not only highlight promising EO-based fumigants against Tribolium castaneum but also provide lead compounds for future structural optimization. Additionally, this discovery strategy serves as a valuable reference for similar studies in natural products and biopesticides.
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危险品化学品经营许可证（带存储）