Journal of Materials Research and Technology-JMR&T
·
2022
·
IF 6.267
Xuefeng Zhang,Huanbo Wang,Zhijun Chen,Shiyu Guo,Yuan Fu,Tian Liu
Fast-growing natural poplar wood is not meet with in many requirements such as high strength and flame retardant due to its porous structure and loose materials. In this study, we established a simple and feasible method that includes delignification, ionic bond formation via the crosslinking of carboxyl groups in TEMPO-oxidized wood after delignification with calcium ions , and hot-pressing of stacked veneers to improve the quality, density, strength, toughness, and weather resistance of natural wood (NW). This method has the following advantages: The inner cellulose microfiber is highly aligned, thus closely cross-linking and tightly bonding cellulose microfibers and nanofibers between the interfaces and inner layers of the wood boards via hydrogen bonding and ionic bonding. A laminated densified TEMPO-oxidized ionic wood (IW) showed substantially higher specific strength (∼196.9 MPa cm3 g−1), higher tensile strength (∼246 MPa), higher flexural strength (∼257 MPa), higher flexural modulus (∼36 GPa), higher impact toughness (∼42.34 kJ m−2), and superior fire retardancy, UV resistance, water resistance, and also higher density (∼1.25 g cm−3) than NW. Larger-size laminated densified structural materials with satisfactory thermal stability can also be fabricated using the proposed method.
研究领域:
材料科学
·
林业工程
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DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2016
·
IF 2.822
Wenbin Zhang,Zhixing Xiong,Yingying Gao,Hang Gao,Ya Zhang
2,2,6,6-Tetramethyl-1-piperidine N -oxyl (TEMPO) and nickel hydroxide (Ni(OH) 2 ) mediated electrooxidation of glycine were performed and roles of bases in these two reactions were investigated by cyclic voltammetry . Trends of 2,4,6-collidine > 2,6-lutidine > 3-picoline > pyridine and KOH > NaOH > LiOH were observed in the studies of bases dependent activities on TEMPO and Ni(OH) 2 mediated glycine electrooxidation, respectively. Base effects can be rationalized by acid neutralization, base assisted deprotonation and the interaction between bases and catalysts.
研究领域:
电化学
·
催化反应
·
分析化学
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产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Hao Zhang,Zhengyuan Tao,Ziqi Yu,Tiantian Zhu,Hanlin Rao,Badusha Mohamad Ali,Jianli Wang
Pickering interfacial catalysts (PICs) have emerged as a promising solution for simultaneously enhancing and catalyzing liquid-liquid biphasic reactions. In this study, we successfully synthesized dumbbell-shaped Janus structured polymeric nanoparticles with one side anchored imidazolium-TEMPO (im-C 4 -TEMPO@JPP) as Pickering interfacial catalyst for the oxidation of alcohols using the Anelli-Montanari reaction system. In the Pickering emulsion system, the im-C 4 -TEMPO@JPPs particles are assembled at the W/O interface due to the hydrophilicity of imidazolium-TEMPO anchored lobe which enables excellent amphiphilic character of the polymeric Janus dumbbell. Moreover, the im-C 4 -TEMPO@JPPs particles reduce the interfacial tension from 27.82 to 18.43 mN/m. This excellent interfacial adsorption capacity of im-C 4 -TEMPO@JPPs strongly stabilizes the water/dichloromethane Pickering emulsion over two months (emulsion volume fraction >90 %), thus providing an efficient reaction platform for liquid-liquid biphasic reactions. As a result, the constructed Pickering emulsion system efficiently catalyzes the oxidation of cinnamyl alcohol to cinnamaldehyde under static conditions. After 1 hour of reaction, the conversion of cinnamyl alcohol achieved 97.1 % with a selectivity of 99 %, nearly the same level relative to stirring intensified biphasic reaction. Hence, this novel PIC effectively improves the efficiency and sustainability of liquid-liquid biphasic catalytic reactions .
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Yuanyuan Yu,Qiang Wang,Jiugang Yuan,Xuerong Fan,Ping Wang,Li Cui
Hydrophobic cotton fabrics were prepared by grafting octadecylamine (ODA) onto cotton fiber surfaces via the laccase/2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) treatment. The cotton fibers were oxidized by laccase/TEMPO to introduce aldehyde groups, which reacted with the amino groups of ODA to form Schiff base. First, ODA was coupled to glucan, used as a model compound of cellulose. The results of FT-IR and MALDI-TOF mass spectroscopy prove the formation of a Schiff base between ODA and glucan. Moreover, the existence of ODA in the grafted cotton fibers was verified by ATR-FTIR, elemental analysis, X-ray photoelectron spectroscopy. Finally, the hydrophobicity of the ODA-grafted cotton fabrics was estimated. The surface hydrophobicity of the cotton fabrics increased after the enzymatic grafting reaction.
研究领域:
材料科学
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纺织工程
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生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CRYSTAL GROWTH
·
2025
·
IF 2
Kang Han,Dandan Gong,Chengwei Du,Lijuan Zhang,Lu Wang,Jing Lian,Aniruddha Majumder,Jie Lu
The influence of 2,2,6,6-Tetramethylpiperidinooxy (TEMPO) cellulose nanofibers (TCNF) on the nucleation and growth of sulfathiazole (STZ) crystals is uncovered, aiding in the precise control of drug crystal morphology. To elucidate the mechanism by which TCNF regulates the nucleation and growth of STZ crystals, cooling crystallization experiments and molecular simulations were conducted. Initially, the crystal forms of STZ in pure water were determined. Subsequently, crystallization experiments with the addition of TCNF were conducted. The experiments aimed to investigate their effects on crystal form and crystal habits. The results revealed that a pure Form III was obtained due to the hydrogen bonding interactions on the surface of TCNF. Molecular simulations helped better explain the influence on specific crystal faces. This study indicates that the influence of TCNF on the characteristics of STZ crystals is mediated through interaction with the z-axis crystal facets, leading to the formation of block-shaped crystals. In addition, the higher concentration of TCNF forms a local closed space, resulting in blocked mobility, allowing STZ molecules in the solution to grow at the defects of STZ crystallization.
研究领域:
药学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2024
·Vol. 16
·期 7
·1016
·
IF 4.7
Nan Jiang,Yudi Hu,Yuhang Cheng
Nanocellulose materials have been widely used in biomedicine, food packaging, aerospace, composite material, and other fields. In this work, cellulose obtained from Camellia shells through alkali boiling and subbleaching was micro-dissolved and regenerated using the DMAc (N,N-Dimethylacetamide)/LiCl system, and TOCNs (TEMPO-oxidized cellulose nanofibers) with different degrees of oxidation. The membrane was prepared by filtration of polytetrafluoroethylene (pore size 0.1 μm), and the oxidized nanocellulose film was obtained after drying, Then, the crystallinity, mechanical properties and oxygen barrier properties of the TOCN film were investigated. Furthermore, based on TS (tea saponin) fromCamellia oleiferaseed cake and TOCNs, TS-TOCN film was prepared by the heterogeneous reaction. The TS-TOCN film not only shows excellent oxygen barrier properties (the oxygen permeability is 2.88 cc·m−2·d−1) but also has good antibacterial effects on both Gram-negative and Gram-positive bacteria. The antibacterial property is comparable to ZnO-TOCN with the same antibacterial content prepared by the in-situ deposition method. Antioxidant activity tests in vitro showed that TS-TOCN had a significant scavenging effect on DPPH (2,2-Diphenyl-1-picrylhydrazyl) radicals. This design strategy makes it possible for inexpensive and abundantCamellia oleiferaremainders to be widely used in the field of biobased materials.
研究领域:
材料科学
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生物医学
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食品科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Xunchun Yuan,Kehang Shi,Haojie Yu,Li Wang,Huanan Wang,Yuan Meng,Hong Yi,Chenguang Ouyang,Md Alim Uddin,Xiwang Yuan,Xinhui Chen,Jianjun Zhang
Magnetic resonance imaging (MRI) is a cornerstone of modern diagnostic imaging. In clinical MRI diagnosis, MRI contrast agents are routinely employed to enhance the image contrast of specific areas in the body. However, conventional metal-based contrast agents pose potential toxicity risks, driving the development of safer metal-free alternatives. Nowadays, nitroxide radical contrast agents have emerged as a promising substitute, offering comparable efficiency without metallic components. In this study, we report three different nitroxide radical (TEMPO)-containing amphiphilic polymers that can self-assemble into spherical nanoparticles in aqueous solution. These nanoparticles exhibit increased longitudinal relaxivities (ranging from 0.58 to 0.88 mM −1 s −1 ), improved stability, and excellent biocompatibility. Following intravenous injection into mice, the nanoparticles produce significant MRI contrast enhancement in the urinary system for at least 1 h. Additionally, the synthesized polymers can function as effective carriers for anticancer drugs. Under reductive conditions, the drug-loaded nanoparticles undergo rapid release, achieving a final cumulative drug release of 62 %. Furthermore, the drug-loaded nanoparticles also show inhibitory effect on Hela cells. Overall, these TEMPO-containing polymer nanoparticles hold significant promise for applications in MRI and stimuli-triggered drug release.
研究领域:
纳米技术
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生物医学工程
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药学
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医学影像学
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高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2026
·
IF 7.8
Fu Danning,Zhang Feifei,Sheng Jie,Wang Lijun,Zhang Xuejin,Li Lin,Hua Feiguo,Jia Zhixin
With the rapid advancement of wearable sensors and the Internet of Things (IoT), self-powered systems have become essential for sustainable, low-maintenance electronics. Triboelectric nanogenerators (TENGs) are promising candidates; however, achieving high electrical output together with mechanical robustness remains challenging. Herein, we report an ultra-tough, stretchable TENG based on a conductive hydrogel reinforced with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibrils (TOCNFs). The design delivers a dual benefit: abundant carboxyl groups on TOCNFs enhance triboelectric charge transfer and boost electrical output, while TOCNFs form a robust triple cross-linked network that imparts durability. The resulting TENG achieves an open-circuit voltage of 69.4 V, a short-circuit current of 2.8 μA, a power density of 12.15 μW/cm 2 , a tensile strength of 3.05 MPa at 908% elongation, and a compressive strength of 4.10 MPa at 80% strain, outperforming most reported hydrogel-based TENGs. For sensing, it exhibits a sensitivity of 0.36 V·kPa –1 , fast response and recovery times (298/270 ms), and stable operation over 5000 cycles. Additionally, the device powers microelectronics, enables wireless Morse-code communication, and supports self-powered health monitoring. This work resolves the common trade-off between performance and durability in TENG design and provides a versatile platform for self-powered wearable electronics and IoT applications.
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产品关联
DOI
PubMed
高影响因子
POLYMER
·
2019
·
IF 3.771
Yadong Lu,Pingbo Zhang,Mingming Fan,Pingping Jiang,Yanmin Bao,Xuewen Gao,Jialiang Xia
An environmentally friendly waterborne polyurethane based on castor oil was prepared and modified by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose microfibers (TOCMF). The TOCMF with surface-attached active carboxyl groups was obtained by TEMPO/NaClO/NaBr system, and then the modified castor oil-based waterborne polyurethane was prepared by the synergistic action of covalent bond and hydrogen bond between TOCMF and prepolymer in the in-situ polymerization reaction . The introduction of carboxylate on the surface of TOCMF facilitated stabilization of the thickness of the double layer of the emulsion particles to form stable WPU/TOCMF dispersions. Benefiting from the filamentous structural effects of TOCMF and the covalent bond and hydrogen bond dual interactions in WPU matrix, WPU/TOCMF composite films showed improvement in tensile strength and thermal decomposition temperature . Tensile strength of composite films increased from 17.89 to 30.31 MPa with increasing TOCMF amount from 0 to 1.00 wt%. T 5% of composite films increased from 202.6 to 239.3 °C with increasing TOCMF amount from 0 to 0.75 wt%. It was observed by SEM that the presence of agglomeration in the composite film with 1.25 and 1.50 wt% TOCMF, and the occurrence of agglomeration caused the performance of the composite film to deteriorate sharply.
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 THE ELECTROCHEMICAL SOCIETY
·
2019
·Vol. 166
·期 12
·A2419
·
IF 3.12
Xianhua Hou,Zishuai Zhang,Kaixiang Shen,Shikun Cheng,Qinyu He,Yumeng Shi,Denis Y. W. Yu,Ching-yuan Su,Lain-Jong Li,Fuming Chen
An anion flow battery has recently emerged as an option to store electricity with high volumetric energy densities. In particular, fluoride ions are attractive for these batteries because they have the smallest size among anions, which is beneficial for charge transport. To date, reported fluoride ion batteries either operate with an ionic liquid, organic electrolyte or solid-state electrolyte at high temperatures. Herein, an aqueous fluoride ion flow battery is proposed that consists of bismuth fluoride as the anode, 4-hydroxy-TEMPO (TEMPO) as the cathode, and NaF salt solution as the aqueous electrolyte. During the charging process, bismuth fluoride electrochemically releases fluoride ions with the formation of bismuth metal, while TEMPO captures the fluoride ions. A reversible and stable discharge capacity of 89.5 mAh g−1 was achieved at 1000 mA g−1 after 85 cycles. The fluoride ion battery possesses excellent rate performance. To the best of our knowledge, this is the earliest demonstration that fluoride ion batteries can work in aqueous solutions, which can be used for future clean energy applications.
研究领域:
能源科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CELLULOSE
·
2025
·
IF 4.8
Ma Hailong,Wang Wenbo,Yu Wei,Kong Fangong,Wang Shoujuan,Liu Keyin,Zhou Zhe,Wei Guijuan,Wang Xiaohui,Liu Yu
Nanocellulose, which can be derived from abundant renewable plant sources, possesses outstanding properties such as nano-size, high strength, and high reactivity, rendering it a promising alternative to fossil-based materials in the future. However, the conventional drying of nanocellulose aqueous suspensions tends to result in significant aggregation, which substantially impedes the functionalization of nanocellulose by organic modifying reagents. This study presents an innovative method for drying nanocellulose from aqueous suspension into ultrafine powders while preserving its nanoscale properties. Ammonium bicarbonate was introduced into the aqueous suspension of cellulose nanofibrils (CNFs) to precipitate CNFs that were then dispersed in n-butanol. During the evaporation process, the ammonium bicarbonate decomposed, and the water evaporated, leading to the drying of CNFs in pure n-butanol into an ultrafine powder with high dispersibility. When prepared with a large amount of n-butanol, these ultrafine powders demonstrate enhanced redispersibility in water, with the ability to form a stable suspension through simple agitation. Our research in this paper centers on elucidating the dispersion mechanism of CNF ultrafine powders. We suggest that CNF ultrafine powders dried from n-butanol form a loosely porous mesoporous structure. In the absence of significant changes in crystallinity, the substantial reduction in the inaccessible area of the amorphous regions is likely responsible for their enhanced redispersibility in water. Additionally, by capitalizing on the micro- and nano-structural characteristics of CNF ultrafine powders, we have successfully developed a superhydrophobic coating by applying hydrophobic modification and adhering the treated powder to the surface of filter paper. This outcome not only substantiates the practical applicability of CNF ultrafine powders but also affirms their micro- and nano-dimensional structural attributes. This paper proposes a straightforward and viable approach for the reaction of functionalized organic reagents with nanocellulose, thereby significantly broadening its potential applications.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ANALYST
·
2011
·Vol. 136
·期 20
·4316-4320
·
IF 3.913
Yang Liu,Mingjiang Zhu,Jingji Xu,Hong Zhang,Mei Tian
Generation of too many reactive oxygen species (ROS) in relation to available antioxidants in living cells can cause oxidative stress, which is involved in the development and progression of several serious diseases. 2′,7′-Dichlorodihydrofluorescein (DCFH) and its diacetate form, DCFH-DA, are widely used probes for monitoring general oxidative stress in cells, but DCFH oxidation is not always related to ROS. We report here a new method for quantifying cellular oxidative stress using a 2,2,6,6-tetramethyl- piperidine-1-oxyl (TEMPO)-based probe. We tested and verified the probe both in cell-free solutions and in living cells under conditions of increased or reduced oxidative stress. The probe revealed the oxidative stress status in living cells and may be a useful complement to DCFH fluorescent probes.
研究领域:
细胞生物学
·
生物化学
·
分子生物学
·
药理学
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）