RSC Advances
·
2016
·Vol. 7
·期 1
·238-247
·
IF 3.289
Xuejuan Yang,Chunpeng Wang,Shouhai Li,Kun Huang,Mei Li,Wei Mao,Shan Cao,Jianling Xia
Two novel bio-based epoxy curing agents derived from myrcene (MMY) and castor oil (CMMY) were prepared, respectively. Their chemical structures were confirmed by Fourier transform infrared spectrometry (FTIR) and 1H nuclear magnetic resonance (1HNMR). The two curing agents were used to cure a commercial epoxy resin (E-51). The MMY-cured epoxy resin had very poor toughness while the CMMY-cured epoxy resin had low strength, so the two curing agents were mixed at different weight ratios to form new curing agents for the E-51 epoxy resin. The tensile strength, impact strength, dynamic mechanical properties, thermal stability, micro-morphology of fracture surfaces and gel content of the cured epoxies were all investigated. The curing behaviors of the cured epoxies were studied by differential scanning calorimetry (DSC). Results show that the elongation at break is increased and the tensile strength and glass transition temperature are decreased with increasing weight ratio of CMMY, while the impact strength is increased gradually. The initial degradation temperatures of all the cured epoxy resins were above 367 °C. The gel contents of the epoxy resins cured with the mixed curing agents were above 87%. The activation energies for the systems with MMY and CMMY were 75.90 and 67.69 kJ mol−1, respectively.
研究领域:
高分子化学
·
材料科学
·
绿色化学
·
复合材料
·
热固性树脂
·
生物基材料
·
聚合物改性
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Xintong Zhou,Chang-jun Liu
Structured porous carbon materials have been extensively applied for catalyst, sensor, adsorbent, energy storage materials and many others. However, the preparation of such carbon materials in a controllable way remains a significant challenge. In this work, 3D printing has been employed to prepare porous carbon structures with tailorable pore sizes. A starch/gelatin ink has been applied as carbon source with SiO 2 monodispersed spheres as hard template. The process exhibits an excellent printing accuracy. Controllable meso and macro structures can be thereby obtained. The printed monolithic structures have been used as metal-free catalysts for the selective oxidation of benzyl alcohol, as an illustration. The monolithic and meso/macro-porous structure has a remarkable influence on the reaction rate. A high conversion with high benzaldehyde selectivity has been achieved. The 3D printing strategy provides us a simple, low cost and reliable way of fabricating carbon structures with designable meso/macro-pores, which is promising for many other applications beyond catalysis.
研究领域:
材料科学
·
催化化学
·
能源材料
·
纳米结构材料
·
功能材料
✓ 已验证
DOI
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
·
2013
·
IF 0.807
Weiwei Xun,Yulin Yi,Chongyin Zhang,Sixun Zheng
In this contribution, we reported the preparation of mesoporous silica with a reactive block copolymer as the porogen via sol-gel process. Firstly, poly(glycidyl methacrylate)-block-poly(ϵ-caprolactone)-block-poly(glycidyl methacrylate) triblock copolymer (PGMA-b-PCL-b-PGMA) was synthesized with the combination of ring-opening polymerization (ROP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. Thereafter, the triblock copolymer was functionalized via its reaction with 3-aminopropyltriethoxysilane (APTES) to afford a new reactive block copolymer bearing triethoxysilane moieties. The latter was employed to perform the inter-component sol-gel reactions with tetraethoxysilane (TEOS) to obtain the organic-inorganic composites with various compositions. The organic-inorganic composites were subsequently used as the precursors to obtain the mesoporous silica materials via pyrolysis at elevated temperatures. The surface-area Brunauer-Emmett-Teller (BET) measurements indicate that the materials of mesoporous silica with adjustable porosity have been successfully obtained.
研究领域:
高分子化学
·
纳米材料
·
生物医用材料
·
多孔材料
·
药物递送系统
✓ 已验证
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2023
·Vol. 17
·期 7
·930-941
·
IF 4.5
Tian Guodong,Duan Chao,Zhou Bingxu,Tian Chaochao,Wang Qiang,Chen Jiachuan
Membrane technology for wastewater remediation has aroused wide interest owing to its unique properties and potential applications. However, it remains challenging to explore green, efficient and robust membrane material and technique for complex wastewater treatment. Herein, we proposed using a simple electrospinning and in situ seeding method to fabricate a lignin-based electrospun nanofiber membrane (LENM) decorated with photo-Fenton Ag@MIL-100(Fe) heterojunctions for efficient separation of oil/water emulsions and degradation of organic dye. Thanks to the embedded lignin in LENM, an ultrahigh MIL-100(Fe) loading (53 wt %) with good wettability and high porosity was obtained. As a result, the hybrid Ag@MIL-100(Fe)/LENM exhibited excellent oil/water emulsions separation efficiency (more than 97%) without a compromise of water flux. Moreover, the hybrid membrane showed an excellent dye removal with degradation of 99% methylene blue within 30 min under illumination, which is attributed to a synergy of dye adsorption/enrichment and photo-Fenton catalytic degradation from Ag@MIL-100(Fe). Therefore, the lignin-based photo-Fenton hybrid membrane can lay the foundation for the preparation and application of green, sustainable and versatile membrane materials and technologies for efficient complex wastewater remediation.
研究领域:
环境科学
·
材料科学
·
化学工程
·
纳米技术
·
水处理技术
✓ 已验证
DOI
高影响因子
JOURNAL OF FLUID MECHANICS
·
2020
·
IF 3.333
Teng Dong,Fei Wang,Weheliye H. Weheliye,Panagiota Angeli
The delayed coalescence of drops with the interface between a moving aqueous layer and an oil phase is investigated in a novel flow channel. Drops are released onto oil–aqueous interfaces moving at velocities from $0~\text{cm}~\text{s}^{-1}$ up to $3.4~\text{cm}~\text{s}^{-1}$. The evolution of the drop shape, the film thickness between the drop and the bulk liquid, and the velocities of the drop surface and the bulk interface were measured with planar laser-induced fluorescence. As the interface speed increases, the drop coalescence is delayed. This is attributed to the lubrication pressure that develops in the draining film. This pressure was calculated by using the drop shape and the tangential velocities of the drop surface and the bulk interface, and was shown to increase with the interface velocity. The film forming between the drop and the bulk liquid has a dimple shape, symmetric about the centreline. With increasing interface velocity, the dimple shifts to the front part of the drop, resulting locally in a low pressure, which leads to film rupture. As the film breaks, ‘oil drops on a string’ formations are entrained into the water phase, which is rarely seen when a drop coalesces with a stationary liquid–liquid interface. The velocity fields in the drop were investigated with particle image velocimetry. It is found immediately after reaching the interface that the drops accelerate to reach the interface speed. Initially there is a strong internal circulation in the drops, which decays quickly as the drops approach the speed of the interface.
研究领域:
流体力学
·
界面科学
·
胶体与界面化学
·
微流控
·
生物医学工程
·
非平衡态物理
·
分子薄膜力学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2016
·
IF 2.835
Zuowang Wu,Chong Chen,Hui Wan,Lei Wang,Zhong Li,Bingxue Li,Qirui Guo,Guofeng Guan
A magnetically recyclable and efficient catalyst for biodiesel synthesis was fabricated by confining the Brønsted ionic liquid 1,4-butanediyl-3,3′-bis(3-sulfopropyl) imidazolium dihydrogensulfate in an amino-functionalized magnetic metal–organic-framework composite (Fe3O4@NH2-MIL-88B(Fe)) through a simple and efficient strategy via the amino groups. The catalyst was systematically characterized, proving ionic liquid was grafted in the amino-functionalized carrier, and the catalyst was spindle-shaped with superparamagnetism (7.2 emu/g). The prepared catalyst with high acidity (1.76 mmol H+ g–1) exhibited good catalytic activity in biodiesel synthesis from oleic acid and ethanol with a yield of 93.2%, optimized by Box-Behnken response surface methodology. The fine catalytic performance of the catalyst was mainly due to the combination of the characteristics of the ionic liquid and the structure of Fe3O4@NH2-MIL-88B(Fe). Moreover, the catalyst was recycled without significant loss of activity after being used for six runs and could be magnetically separated in magnetic force without obvious mass loss.
研究领域:
催化化学
·
能源材料
·
绿色化学
·
纳米复合材料
·
可再生能源
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2017
·
IF 4.529
Ting Shi,MengTing Zhu,Yi Chen,XiaoLi Yan,Qian Chen,XiaoLin Wu,Jiangnan Lin,Mingyong Xie
Proton nuclear magnetic resonance ( 1 H NMR) and chemometrics were employed to detect the adulteration of camellia oil (CAO) with 3 different cheap vegetable oils. With the intensity of 15 selected 1 H NMR signals as input variables, principal component analysis (PCA) showed good group clustering results for pure and nonpure CAO, but unsatisfied identification accuracy for the adulterated oil types, indicating relatively small difference among those oils. Whereas these difference could be revealed by orthogonal projection to latent structures discriminant analysis (OPLS-DA), with identification accuracy higher than 90%. Partial least squares (PLS) was further applied for the prediction of adulteration level in CAO. With less than 6 variables screened out by variable importance in the projection (VIP) scores as potential key markers, the developed PLS models showed better accuracy. The prediction results for 10 hold-out samples also confirmed that this method was accurate and fast for the detection of CAO adulteration.
研究领域:
食品科学
·
分析化学
·
食品安全
·
代谢组学
·
油脂化学
✓ 已验证
DOI
高影响因子
COMBUSTION AND FLAME
·
2021
·
IF 4.185
Zhi-Hao Jin,Jin-Tao Chen,Wang Li,Shu-Bao Song,Jiu-Zhong Yang,Zhen-Yu Tian
Owing to significant advantages over traditional biofuels, 2-methylfuran (MF) has arisen extensive interest as next generation biofuels . Atmospheric pressure pyrolysis of a 1:1 blend of MF with a three-component (3C) surrogate jet fuel was conducted in a flow tube using synchrotronphotoionization and molecular beam mass spectrometry techniques within a temperature range of 898–1223 K. Therein, the 3C surrogate fuel consists of 66.2% n-dodecane (NC 12 H 26 ), 18.0% 1,3,5-trimethylcyclohexane (T135MCH) and 15.8% n-propylbenzene (NPB, A1C 3 H 7 ). The detailed kinetic model including 579 species and 3474 reactions was developed via validating against both measured and literature data with reasonable agreement. MF exhibits no obvious influence on the 3C components pyrolysis . However, 3C mixtures play an important roles in MF decomposition: lower initial temperature and different decomposition pathways. In the meantime, n-propylbenzene (NPB) pyrolysis curve in 3C and 3C+MF significantly transfers to low temperature zone after 1000 K in contrast to pure NPB, while smaller change was found in the decomposition curve of n-dodecane. Compared with 3C pyrolysis, 3C+MF blends have less formation of aromatic species and light hydrocarbons except for vinylacetylene (C 4 H 4 ) and acetylene (C 2 H 2 ). Allyl radical (C 3 H 3 ) has significant roles in benzene ring formation. The combination of allyl radical with propargyl radical producing benzene and H radical (aC 3 H 5 + C 3 H 3 = A1 + 2H) has the highest contribution to the benzene formation in both 3C and 3C+MF. Moreover, most of naphthalene (A2) formation is also related to C 3 H 3 radical via reaction: A1CH 2 + C 3 H 3 = A2 + H, rather than via HACA (hydrogen abstraction carbon addition) reaction. Interaction of fuel blends was mainly presented through the common and important sensitive reactions which are much to do with CH 3 and H radicals. The overview of product distribution was investigated by providing comparisons of carbon conversion rates during the pyrolysis of 3C and 3C+MF. These results will be helpful to better understand the pyrolysis properties of MF/jet fuel surrogate blends and could contribute to developing new generation biofuels for aviation.
研究领域:
燃料化学
·
燃烧动力学
·
生物燃料
·
能源化学
·
反应机理
·
质谱分析
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2016
·
IF 3.847
Yong-gang Wang,Guang-ce Jiang,Sheng-juan Zhang,Hai-yong Zhang,Xiong-chao Lin,Xin Huang,Mao-hong Fan
The selectivity of organic solvent extraction for separating non-aromatic hydrocarbons, aromatic hydrocarbons and polar components in low-temperature coal tar was enhanced by applying the Hansen Solubility Parameters theory. The relationship between solubility parameter “distance” ( R a ) and solubility was obtained by turbidimetric titration, thus allowing an approximate comparison of dissolving properties between different solvents and the typical model compound (solute). A modified dissolving model in terms of the Hansen solubility sphere was established in order to select the extraction solvent. In practice, the low-temperature coal tar was successfully divided into three parts (i.e., enriching non-aromatic hydrocarbons, aromatic hydrocarbons and polar components) by a three-step extraction-precipitation process at 298 K and 1 atm. Experimental results demonstrated a high correlation with the estimation made by the ellipsoidal model. The mass percentage of non-aromatic hydrocarbons, aromatic hydrocarbons and polar components in their separation products were all ca. 90 wt.%. The mass percentages of the three products in total feedstock were around 12%, 46% and 36%, respectively. The mass loss during the entire separation process was from 4.5% to 6.0%.
研究领域:
能源化学
·
煤化工
·
分离科学
·
物理化学
·
应用化学
·
材料化学
·
过程工程
✓ 已验证
DOI
高影响因子
COMBUSTION AND FLAME
·
2021
·
IF 4.185
Jizhen Zhu,Sixu Wang,Mohsin Raza,Yuan Feng,Jing Li,Yebing Mao,Liang Yu,Yong Qian,Xingcai Lu
Methanol is an attractive oxygenate increasingly used as primary fuel for dual-fuel combustion technology yielding beneficial thermal-efficiency and emissions in modern engines. As such, it is significant to fundamentally understand the autoignition behavior of methanol/diesel mixtures. This study measured the ignition delay times (IDTs) of methanol/diesel blends with different mixing ratios (30%, 50%, 70% methanol by mol.) on a heated shock tube and a heated rapid compression machine at temperatures of 650−1450 K, pressures of 6−20 bar, and equivalence ratios of 0.5, 1.0 and 2.0. The typical two-stage ignition characteristics with the negative temperature coefficient response were observed for dual-fuel mixtures. In general, both the total and first-stage IDTs decrease with the increment of pressure and equivalence ratio as well as diesel proportion in mixtures. The simulation results performed with a published detailed mechanism in conjunction with a tri-component diesel surrogate demonstrate generally good agreement with the experimental data at all test conditions. Moreover, a crossover of IDTs occurs at a higher temperature (~1500 K) for varying equivalence ratios, and experiment and simulation both exhibit a non-linear mixing effect of methanol addition on diesel ignition. Interestingly, simulation results clearly suggest a crossover (~940 K) for mixtures with varying methanol content at an intermediate-temperature, where the IDT of the mixture with a lower methanol ratio becomes longer as the temperature is higher than that of the crossover. Furthermore, brute-force sensitivity analyses assisted with reaction path analysis were conducted to gain deeper insights into the autoignition chemistry of dual-fuel mixtures, especially for the chemical interaction between both fuels during the low-temperature oxidation process . It is found that methanol hardly generates •OH, whereas •OH is mainly produced by the low-temperature reaction pathways of diesel. Thus, •OH is the bridge for both fuels during the ignition process. At the high methanol ratio, the H-abstraction of diesel is mainly via •HO 2 while CH 3 OH consumes a large percentage of •OH. Consequently, the competition between methanol and diesel for •OH radicals inhibits the overall reactivity of reaction network. In addition, the original data reported here lay a foundation for the development and validation of more accurate and robust dual-fuel kinetic schemes.
研究领域:
燃烧化学
·
燃料科学
·
化学动力学
·
内燃机工程
·
替代燃料技术
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2022
·Vol. 24
·期 3
·69
·
IF 2.533
Song Rong,Li Ying,Qian Jun
Perovskite has shown attractive optoelectronic performances and is a potential material in lighting, anti-counterfeiting, sensor, and other optoelectronic devices. Recently, spin-coating has been widely used in fabricating high-performance perovskite films, but it is difficult to process and apply in practice. In this paper, the CsPbBr 3 /Cs 4 PbBr 6 composite perovskite quantum dots with photoluminescence quantum yield of 36% and high storage stability were prepared by using room temperature ligand-assisted precipitation method and controlling the proportion of CsBr/PbBr 2 . In addition, the composite perovskite was ground and dispersed in the inks system. After adjusting the composition and ratio of the resin components, the inks were suitable for screen printing with a viscosity of 2439 mPa•s, an initial dryness of 25 mm/30 s, and a thorough dryness of 100 s/100 μm. By printing, the perovskite films exhibited high coverage, strong green emission, and outstanding fluorescence recovery ability after exposure to water. Screen printing perovskite inks have the characteristic of being patternable, which provides a solution for preparing a perovskite film in the application.
研究领域:
材料科学
·
纳米科技
·
光电子学
·
印刷电子
·
荧光材料
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Weiyi Zhang,Haozhen Zhang,Xinglian Xu,Xue Zhao
The oil polarity was hypothesized to significantly influence the microscopic conformation of interfacial myofibrillar protein (MP) and thus the mesoscopic interfacial rheology of MP film , which ultimately tuned the macroscopic stability of MP-stabilized emulsions. In this research, the inner mechanism was revealed hierarchically based on emulsions multi-scale properties, by a combination of in vitro interfacial concentration measurement, dynamic interfacial tension measurement and interfacial dilatational rheology (highlighting Lissajous plots). Then, the above conclusion was verified through in silico molecular dynamic simulation. At macroscopic level, the light scattering results showed that emulsion prepared with higher polarity oil exhibited higher physical stability. This could be explained from the mesoscopic perspective that: (1) the adsorption dynamics of MP was faster (though lower diffusion rate, but higher penetration and rearrangement rate) on the higher polarity interface, which decreased interfacial tension more efficiently; (2) adsorption ratio, surface load and desorption ratio indicated that ‘multilayer interfacial film’ was formed by loosely-bound MP on the lower polarity interface, which decreased the effective interfacial coverage to impair emulsions stability; (3) Lissajous plots showed that interfacial structure with higher stability against large deformation was formed on the higher polarity oil interface. Finally, the microscopic molecular mechanism for explaining the above findings was revealed by in silico molecular dynamic simulation: though MP was less unfolded on the higher polarity interface leading to weaker intermolecular hydrophobic interactions, this compact molecular structure with stronger intramolecular rigidity predominantly contributed to steadier interfacial film structure. This multi-scale study provides a deep insight into the inner relationship between oil polarity and emulsions stability.
研究领域:
食品科学
·
胶体与界面化学
·
蛋白质构象
·
软物质物理
·
分子模拟
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）