Analytical Methods
·
2016
·Vol. 8
·期 24
·4926-4933
·
IF 1.915
Dejiang Rao,Qinglin Sheng,Jianbin Zheng
Herein, we report a simple and attractive self-assembly strategy for preparing graphene oxide–multiwalled carbon nanotube–(1-pyrenemethylamine)–gold (GO–MWCNT–PMA–Au) nanocomposites using 1-pyrenemethylamine (PMA) as a coupling agent. The morphology and composition of the nanocomposites were characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS). Further, a non-enzymatic nitrite sensor was fabricated by immobilizing GO–MWCNT–PMA–Au nanocomposites on a glassy carbon electrode (GCE). To obtain the optimal electrochemical experimental conditions, the effects of pH value and the volume of the as-prepared Au nanoparticle suspension were carefully investigated. Its electrochemical sensing properties were studied by cyclic voltammetry and differential pulse voltammetry. The electrochemical investigation showed that the GO–MWCNT–PMA–Au nanocomposites exhibited good catalytic performance for the oxidation of nitrite. The nitrite electrochemical sensor presented a wide linear range from 2.0 × 10−6 to 1.0 × 10−2 mol L−1, a high sensitivity of 483.51 μA mM−1 cm−2 and a low detection limit of 0.67 μmol L−1 at a signal-to-noise ratio of 3 (S/N = 3). It also exhibited good anti-interference capability and stability. This paper provides a self-assembly strategy for preparing nanocomposites which are used to construct improved electrochemical sensors.
研究领域:
分析化学
·
纳米生物技术
·
电化学传感
·
环境监测
·
食品安全
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2024
·
IF 3.7
Xiaofei Xu,Xiaolong Li,Zhi Li,Da Zhang
An experimental study of single carbon dioxide (CO 2 ) bubbles ascending in aqueous solutions of carboxymethyl cellulose (CMC) is performed as a means to obtain further understanding of the rising behavior and mass transfer of soluble bubbles in shear-thinning non-Newtonian fluids. High-speed photography and digital image processing technique are employed to quantify the characteristic parameters of the bubble rising process. The rising behavior of single CO 2 bubbles in a Newtonian fluid (tap water) is measured as a reference. It has been found that the rheology of the liquid phase significantly influenced the rising behavior of the bubbles. In CMC aqueous solutions, CO 2 bubbles mostly followed a straight rising path characterized by increasing aspect ratio and decreasing vertical velocity. Increase in initial bubble size led to bubble deformation in less concentrated CMC aqueous solutions which resulted in an irregular rising path. The evolution of bubble equivalent diameter can be mainly divided into two stages: a fast reduction stage followed by a slow one. Meanwhile, the variation of liquid-side mass transfer coefficient k L of CO 2 bubbles in tap water and CMC aqueous solution with different weight percentages is discussed. The mobility of gas-liquid interface is considered to have significant impact on gas-liquid mass transfer. A dimensionless correlation considering the rheology of the liquid phase is proposed to describe the evolution of the motion and deformation of single soluble CO 2 bubbles in infinite stagnant shear-thinning non-Newtonian liquids.
研究领域:
流体力学
·
化学工程
·
多相流
·
传质过程
·
非牛顿流体动力学
·
气泡动力学
·
环境工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Zhenzhen Yang,Renliang Huang,Wei Qi,Liping Tong,Rongxin Su,Zhimin He
Reduced graphene oxide functionalized with magnetic Fe 3 O 4 nanoparticles and –PhSO 3 H groups (Fe 3 O 4 -RGO-SO 3 H) was reported for environmentally benign hydrolysis of cellulosic materials, which is an important process in integrated utilization of biomass resource. Except for –PhSO 3 H groups, –COOH and –OH groups derived from graphene oxide (GO) were also expected in the structure of Fe 3 O 4 -RGO-SO 3 H. Fe 3 O 4 -RGO-SO 3 H exhibited outstanding catalytic performance for the hydrolysis of cellulosic materials, due to its crumpling feature with clear layers and the coexistence of –COOH and –OH groups. The unique structure of Fe 3 O 4 -RGO-SO 3 H favors the accessibility of cellulose to the active sites of the material and facilitates the diffusion of the product molecules. –COOH groups on the surface of the material provide a large concentration of acidic functionality for hydrolyzing cellulose, while –OH groups readily adsorb cellulose through forming strong hydrogen bonds between –OH groups and the oxygen atoms in β-1,4 glycosidic bonds. Furthermore, Fe 3 O 4 -RGO-SO 3 H can also be easily separated from the reaction residue with an extra magnetic force and further used at least five times.
研究领域:
材料化学
·
催化化学
·
生物质能源
·
绿色化学
·
纳米材料科学
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·Vol. 12
·期 6
·5421-5430
·
IF 1.5
Yangyang Xi,Peng Zhang,Haining Zhang,Zhaohui Wan,Wenmao Tu,Haolin Tang
Composite membrane separators are fabricated by coating one side of microporous polyethylene membrane with poly(methyl methacrylate) modified titanate nanoparticles that are synthesized through emulsifier-free emulsion polymerization of methacrylate-functionalized titanate nanoparticles. The formed composite membrane separators exhibit great thermal-shrinking resistance due to the introduction of thermal resistant titanate nanoparticles. After immersed into electrolyte solution, the swelling poly(methyl methacrylate) microspheres leads to the formation of gel electrolyte, thus stabilizing the electrolyte. Moreover, the porous structure of the coated layer can facilitate the swelling of electrolyte and the transport of lithium ions. The thus-assembled lithium ion battery shows an improved cycle performance and rate capability.
研究领域:
材料科学
·
电化学
·
能源存储
·
高分子纳米复合材料
·
电池技术
✓ 已验证
DOI
高影响因子
Advanced Healthcare Materials
·
2024
·Vol. 14
·期 1
·2402272
·
IF 10
Hongwei Zhang,Linfu Chen,Qian Chen,Qiufang Chen,Jun Zhou
Tirapazamine (TPZ), an antitumor prodrug, can be activated in hypoxic environment. It specifically targets the hypoxic microenvironment of tumors and produces toxic free radicals. However, due to the tumor is not completely hypoxic, TPZ often fails to effectively treat the entire tumor tissue, resulting in suboptimal therapeutic outcomes. Herein, a low pathogenic Escherichia coli TOP10 is utilized to selectively colonize tumor tissues, disrupt blood vessels, and induce thrombus formation, leading to the expansion of hypoxic region and improving the therapeutic effect of TPZ. Additionally, a thermosensitive hydrogel is constructed by Pluronic F-127 (F127), which undergoes gelation in situ at the tumor site, resulting in sustained release of TPZ. To monitor the therapeutic process, it is genetically modified TOP10 by integrating the bioluminescent system luxCDABE (TOP10-Lux). The bioluminescent signal is associated with tumor hypoxia enhancement and thrombus formation, which is beneficial for therapeutic monitoring with bioluminescence imaging. In the murine colon cancer model, the TOP10-Lux combined with TPZ-loaded F127 hydrogel effectively suppressed tumor growth, and the treatment process is efficiently monitored. Together, this work employs genetically modified TOP10-Lux to enhance the therapeutic efficacy of TPZ and monitor the treatment process, providing an effective strategy for bacteria-based tumor-targeted chemotherapy and treatment monitoring.
研究领域:
肿瘤学
·
微生物治疗
·
分子影像学
·
药物递送
·
生物材料
·
转化医学
·
合成生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2016
·
IF 6.333
Fanli Meng,Yi Luo,Yali Zhou,Jinwen Zhang,Yanzhen Zheng,Guozhong Cao,Xia Tao
A plasmon-enhanced upconversion composite Y 2 O 3 :Er/Au@TiO 2 (SYE/A@T) with a three-dimensional starlike morphology is prepared and then mixed with submicron TiO 2 (200 nm) to form a multifunctional scattering layer in TiO 2 -based dye-sensitized solar cells (DSSCs). In such starlike micronsized upconverter, Au nanoparticle-assisted plasmon effect can intensify the upconversion emission of Y 2 O 3 :Er, and simultaneously TiO 2 coating can improve the charge transport within SYE/A@T. Therefore, the SYE/A@T shows extended light-absorbing range to near-infrared region and improved light-scattering ability, leading to an improved photovoltaic performance of DSSCs. With the optimum mixing ratio, a conversion efficiency of 8.62% is attained, which is a significant improvement of 27.6% compared with the cell without adding SYE/A@T. Our work provides a feasible strategy to prepare an upconversion composite with plasmon-enhanced emission and enable this composite to accommodate the DSSCs system and improve the conversion efficiency of DSSCs.
研究领域:
材料科学
·
光伏技术
·
纳米光学
·
能源材料
·
表面等离激元
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 141
·期 10
·e55068
·
IF 3
Zhu Mian,Wang Bin,Lv Chao,Yu Zhenhui,Jingxian Liu
Gas separation membranes offer a cost-effective solution for capturing greenhouse gases, mitigating the global greenhouse effect. Ionic liquids (ILs) have emerged as one of the promising materials for greenhouse gas separation due to their strong affinity for CO 2 . In this study, we propose a laboratory-scale method for preparing IL–PVDF blend membranes with high CO 2 /N 2 selectivity. The separation performance of the membranes was evaluated using a custom gas permeation measurement system. The effects of casting solution composition, solidification method, and film-forming processes on separation performance were experimental investigated, and the obtained experimental data were used to train a back propagation neural network (BPNN) optimized by the Gray Wolf Optimizer (GWO) algorithm. This hybrid GWO–BPNN model was utilized to predict separation membrane efficiency, optimize the film-forming process, and identify the optimal range of process parameters. Notably, the GWO–BPNN model demonstrated a 2.76% higher prediction accuracy compared to a standalone BPNN. The results indicated that the GWO–BPNN algorithm has a great potential to accurately predict membrane separation efficiency and apply in optimal membrane process design (OMPD), and this method can significantly reduce the number of experimental trials required to achieve OMPD.
研究领域:
材料科学
·
化学工程
·
环境科学
·
膜分离技术
·
计算材料学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·Vol. 44
·期 2
·1731-1736
·
IF 2.986
Jingbo Yu,Qian Zhang,Yi Gu,Anxian Lu
In this study, phosphate glasses embedded with Fe 2 O 3 quantum dots were prepared via a conventional melt quenching technology with further heat treatment. The effect of Fe 2 O 3 content on the structural, optical and magneto-optical properties was investigated. The results showed that the addition of Fe 2 O 3 had no obvious influence on the structure units that built up the host glass and the amorphous nature of glass. In the glass matrix , the existence of Fe 2 O 3 quantum dots was confirmed by high resolution transmission electron microscope . Meanwhile, optical study clearly demonstrated a red shift in optical cut-off wavelength resulted from the size quantization effect. The highest Verdet constant (22.33°/T-cm) was measured for the glass containing 1 mol% Fe 2 O 3 , which was ~ 7 times higher than that of the glass matrix. As the increment of Fe 2 O 3 contents, a phase evolution of Fe 2 O 3 quantum dots from amorphous phase to γ-Fe 2 O 3 phase was recorded due to the Ostwald Ripening effect. Interestingly, a concentration quenching phenomenon in Verdet constant was observed along with the phase evolution of Fe 2 O 3 quantum dots. When the content of Fe 2 O 3 is up to 2 mol%, the glass exhibited paramagnetism with the Verdet constant of − 2.833°/T-cm. This finding can provide a new idea for the development of quantum dot embedded magneto-optical glass.
研究领域:
材料科学
·
磁光材料
·
纳米材料
·
无机非金属材料
·
光学玻璃
·
凝聚态物理
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2020
·Vol. 221
·期 14
·2000144
·
IF 2.335
Guangfa Shi,Xiaomin Cai,Wenqiang Wang,Gengchao Wang
Polymeric positive temperature coefficient (PTC) materials can be used to install “brake” technology for the thermal runaway of lithium-ion batteries. However, it still has poor cycle stability and obvious negative temperature coefficient (NTC) effect, which reduces the reliability of the material. In order to solve these problems, conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) modified multilayer graphene (MLG) conductive additive (PEDOT-MLG) is introduced into middle density polyethylene/carbon black (MDPE/CB) system. Compared with the conventional modification, the PEDOT modified MLG shows high conductivity and excellent thermal stability. In addition, the introduction of PEDOT-MLG into MDPE/CB can further reduce the room temperature resistivity due to the good compatibility between the modified graphene and the matrix, thus improving the PTC intensity to 7.1. What is more, MLG limits the re-aggregation of CB particles when the temperature further rises, which effectively weakens the NTC effect.
研究领域:
高分子材料科学
·
功能材料
·
能源材料
·
纳米复合材料
·
电学性能
·
锂离子电池安全
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 46
·期 16
·25802-25807
·
IF 3.83
Jun Xiao,Yan Jia,Dongqing Liu,Haifeng Cheng
Manufacturing complexity and poor machinability hinder the preparation of complex-shaped ceramic composites. Three-dimensional printing can overcome this difficulty. Herein, we report a type of photocurable preceramic resin containing SiO 2 nanoparticles (up to 20 wt% of polymer), which do not affect the photocurability of the preceramic resin, and a small amount of SiC nanofibres (1 wt%). We successfully printed precise green bodies with a complex shape by digital light processing and converted them into ceramic composites via pyrolysis at 1300 °C under a N 2 atmosphere. The introduction of SiO 2 and SiC into the ceramic composites led to reduced weight loss of the composites during pyrolysis and a decrease in their porosity and enhancement in their mechanical properties after pyrolysis. The properties of the printed samples pyrolysed at different ramping rates were compared, and the effects of the microstructure on the mechanical properties of the composites were investigated.
研究领域:
材料科学
·
陶瓷工程
·
增材制造
·
高分子转化陶瓷
·
复合材料
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·Vol. 43
·期 45
·20712-20720
·
IF 4.229
Biyao Jin,Yiqi Li,Lianhua Zhao
Bimetallic PdV/C nanoparticles have been synthesized by phase-transfer method for catalyzing the oxygen reduction reaction (ORR) in alkaline electrolytes . PdV/C nanoparticles with different V contents are spherical with a mean diameter of 3–4 nm, and the addition of V expands the lattice parameter of Pd as shown by XRD . XPS analysis indicated the binding energy of Pd 0 3d peak increased by ca. 1 eV. Density functional theory (DFT) calculations results shows d-band center of Pd down-shift after V-doping. Based on the electrocatalytic results, introducing V can improve the catalytic activity for ORR, methanol crossover tolerance and stability. Especially, Pd 4 V/C shows higher initial potential (E onset = 1.027 V), excellent methanol crossover tolerance (98.03% retained) and long-term stability (81.30% retained), which are comparable with Pt/C JM . This work provides a new method of synthesizing PdV/C nanoparticles , which have the potential to be used as the cathode electrocatalysts for fuel cells.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源材料
·
燃料电池
·
物理化学
·
表面科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Shiyuan Chen,Junheng Zhang,Jiliang Zhou,Daohong Zhang,Aiqing Zhang
A novel hyperbranched polymeric ionic liquid (HBP-AMIM + PF6 − ) was explored via a thiol-ene click reaction using thiol-ended hyperbranched polyesters (THBP) and 1-allyl-3-imethylimidazolium hexafluorophosphate (AMIMPF6). The effects of HBP-AMIM + PF6 − on the curing behavior, mechanical properties and thermal stability of benzoxazine/epoxy thermosets were investigated. The gelation time and differential scanning calorimetry of non-isothermal analysis indicated that the addition of HBP-AMIM + PF6 − significantly decreased the curing temperature of benzoxazine/epoxy thermosets. Simultaneously, the addition of HBP-AMIM + PF6 − also improved the strength, toghness and thermal properties of benzoxazine-epoxy thermosets. The addition of 3 wt% HBP-AMIM + PF6 − -2 could significantly improve the mechanical and thermal performance of thermosets compared with that of cured neat benzoxazine/epoxy resin. The tensile strength, tensile toughness, flexural strength and flexural modulus, impact strength of the thermosets were improved by about 76.6%, 279.3%, 57.8%, 22.3% and 80.4%, respectively, compared with those of cured neat resin. The toughening mechanisms was attributed to the “in situ” reinforcing and toughening mechanism.
研究领域:
高分子材料
·
材料科学
·
热固性树脂
·
复合材料
·
高分子化学
·
功能材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）