JOURNAL OF MOLECULAR LIQUIDS
·
2021
·
IF 6.165
Jing Fan,Liangliang Fan,Shuangshuo Liu,Fenhong Song
Globally, biofuel is considered as the largest renewable energy source to substitute the petrochemical fuel and it is thus received a great amount of attention from both developed countries and developing countries. Among all the biofuels, biodiesel is strongly recommended as a promising alternative fuel for traditional internal combustion engines. Thermal conductivity is an essential transport property of fuel, and is vital in the flow and heat transfer process. Therefore, it is necessary to conduct the research associated with fuel’s thermal conductivity . In this work, four binary fuel mixtures containing biodiesel components methyl caprate and ethyl caprate with n-undecane and n-tridecane were prepared respectively, and the liquid thermal conductivity of which were measured by the transient hot wire method system. The measurement was conducted at the temperature from 292 K to 362 K at atmospheric pressure. The experimental data reported here have an uncertainty of less than 2%. In addition, a correlation about the relationship between the liquid thermal conductivity with temperature and the esters’ concentration in different fuel blends has been correlated.
研究领域:
燃料化学
·
热物理性质
·
可再生能源
·
生物燃料
·
传热传质
✓ 已验证
DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2022
·Vol. 39
·期 1
·315-324
·
IF 6.535
Qianjin Lin,Wanxiong Liao,Jia Cheng,Chun Zou,Bin Yang,Wenxiang Xia
Few studies on the low-temperature combustion behavior of MIPK, being a promising fuel additive , have been conducted. In this work, ignition delay times (IDTs) of MIPK were measured in the temperatures ranging between 780–910 K and pressures of 20 and 25 bar using a rapid compression machine (RCM). Oxy-fuel combustion combined with biofuel could remove CO 2 from the atmosphere. The IDTs of MIPK were measured in the temperatures ranging between 1125–1600 K under the O 2 /CO 2 atmosphere at the pressures of 1 and 10 bar using a shock tube . A low to high-temperature MIPK kinetic model (HUST-MIPK model) was proposed, in which the low-temperature sub-model consists of 19 low-temperature reaction classes and was constructed by analogy-based method, the high-temperature sub-model was adapted from the works of Cheng et al.. The predictions of HUST-MIPK model are in good agreement with the present low-temperature IDTs, high-temperature O 2 /CO 2 atmosphere IDTs, and the literature experimental data. The negative temperature coefficient (NTC) behavior was not observed in the temperature range from 790 to 910 K in the present RCM experiments, but was observed for methyl propyl ketone (MPK) and diethyl ketone (DEK) under similar conditions. The low-temperature chemistry of three pentanone isomers (MIPK, MPK, and DEK) was compared using the flux and sensitivity analysis. The comparison of the experimental high-temperature IDTs between O 2 /CO 2 and O 2 /Ar atmospheres indicates the IDTs of MIPK under O 2 /CO 2 atmosphere are longer than those under O 2 /Ar atmosphere at 1 bar, and the effects of CO 2 are almost independent of the pressure. The physical and chemical effects of CO 2 on the ignition were studied in detail.
研究领域:
燃烧化学
·
燃料化学
·
反应动力学
·
能源工程
·
大气环境影响
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2019
·
IF 3.413
Shuzhen Yang,Yanfang Huang,Shengpeng Su,Guihong Han,Jiongtian Liu
A hybrid water-soluble humics-based binder (humics/sodium carboxymethyl cellulose (CMC)) was studied to enhance the electrochemical performance of a Li-ion battery cathode (LiFePO 4 ) in this work. Molecular dynamics simulations of binder active fractions with related materials (LiFePO 4 and Al) were performed to explore the binding mechanisms. Humics serve to connect the active material and provide a conducting bridge in the cathode. To improve the adhesion between the particles and current collector, CMC is added as an auxiliary fraction with a mass ratio of humics to CMC of 3:1. The scanning electron microscope results indicate that the morphology of the electrode with the hybrid humics/CMC binder is more uniform than that of electrodes with conventional polyvinylidene fluoride and CMC binders. The electrochemical performance and cycling stability of the cathode materials are obviously enhanced. The reversible specific capacity can reach 152.3 mAh g −1 at 0.5 °C after 100 cycles. The rate capability is greatly improved, with a specific capacity as high as 105 mAh g −1 at 8 °C. The humics/CMC composite can be regarded as a novel, environmentally friendly and high-efficiency binder for application in Li-ion batteries.
研究领域:
电化学
·
材料科学
·
能源存储
·
纳米材料
·
可持续能源技术
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 65
·52382-52387
·
IF 3.84
Minxia Li,Xiaowei Wang,Yanfang Wang,Bingwei Chen,Yuping Wu,Rudolf Holze
A new composite gel polymer electrolyte of nonwoven fabric (NWF) and methyl cellulose (MC) with good mechanical properties and outstanding thermal and electrochemical stability is prepared by a simple and green casting process followed by absorbing liquid electrolyte. Its characteristics are investigated by scanning electron microscopy, FT-IR, thermogravimetric analysis (TGA). Due to the synergistic action between MC matrix and the NWF framework, the composite gel polymer electrolyte achieves higher ionic conductivity (0.29 mS cm−1) at ambient temperature and larger lithium ion transference number (0.34) than those for the conventional Celgard 2730 separator (0.21 mS cm−1 and 0.27, respectively) in 1 mol L−1 LiPF6 electrolyte, and their activation energies are similar. In addition, the composite membrane shows better mechanical strength than the pure MC membrane. The evaporation rate of the liquid electrolyte at elevated temperature is much decreased. The assembled Li//LiFePO4 cell using this composite gel membrane exhibits better cycling retention and higher discharge capacity than those based on Celgard 2730 separator and pure MC gel membrane. These fascinating characteristics suggest that this unique composite gel polymer electrolyte can be used for lithium ion batteries with good performance and low cost.
研究领域:
材料科学
·
电化学
·
能源存储
·
高分子材料
·
电池技术
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2018
·Vol. 29
·期 12
·2982-2991
·
IF 2.137
Zhiyong Zhang,Miaojun Xu,Bin Li
The polymethacrylimide/silicate (PMI/silicate) composites were successfully prepared from the monomers of acrylonitrile (AN) and methacrylic acid (MAA) via the monomer in situ intercalation polymerization and free foaming. The formation of imide groups was monitored by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results of FTIR and XPS indicated that the imide groups were gradually formed and cyano groups were dwindling but still existed during foaming and thermal treatment. The thermogravimetric analysis results revealed that the thermal stability of the PMI/silicate composites was improved, the rate of thermal degradation was reduced, and the residue was increased because of the addition of silicates. The results of dynamic mechanical analysis revealed that the rigidity and the glass transition temperature of the composites were improved. The limit oxygen index (LOI) and cone calorimeter (CONE) test showed that the fire-retardant properties were improved because of the barrier effect of silicates. The cell morphologies of the PMI/silicate composites were characterized by scanning electron microscopy (SEM), and the results showed that the silicate particles were distributed on the cell walls, but the cells slightly cracked. The mechanical properties were measured by tensile, flexural, and compressive strength. The mechanical strength, especially flexural strength, was significantly improved. The flexural strength of PMI/MMT, PMI/kaolin, and PMI/talc containing 8 wt% silicates was improved to 172%, 240%, and 233%.
研究领域:
高分子材料
·
复合材料科学
·
材料化学
·
防火材料
·
多孔材料
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2022
·
IF 3.656
Liang Qin,Yan Li,Deyun Ma,Fenglan Liang,Lidian Chen,Chenyang Xie,Jiayong Lin,Yani Pan,Guizhen Li,Fenrou Chen,Peiru Xu,Canlin Hong,Jiaxing Zhu
Two transition metal-based MOFs , {[Ni 2 (pip) 2 (bimb) 1.5 ]·2(H 2 O)} n ( 1 ), and {[Zn(pip)(bimb)]·DMF} n ( 2 ) (pip = 5-phenyl-isophthalate, bimb = 1,4-bis(imidazole-1-ylmethyl)benzene) have been successfully prepared. Complex 1 displays a three-dimensional structure with a 7-connected svk topology with a point symbol of (3 3 ∙4 14 ∙5 3 ∙6). Complex 2 performs a two-dimensional (4,4) sql net with channels of 7.0 × 5.5 Å 2 and 10.5 × 4.7 Å 2 along the b and c axis, respectively. The magnetic result of 1 shows an antiferromagnetic coupling between the two metal centers. Desolvated 2 adsorbs around 15.25 wt% 5-fluorouracil (5-FU). The 5-FU was slowly released without any burst release. The degradation of methyl orange caused by oxidizing sulfate radicals (SO 4− ) in a Fenton-like process has also been explored.
研究领域:
无机化学
·
材料科学
·
药物递送
·
环境催化
·
配位化学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2016
·
IF 8.328
Jing Guo,Shanhui Zhu,Youliang Cen,Zhangfeng Qin,Jianguo Wang,Weibin Fan
A series of ordered mesoporous Nb x W (8 − x) oxides with tunable Nb/W ratio were successfully synthesized by evaporation-induced self-assembly method. The mesoporous structure, morphologies, surface chemical state, and acidic properties of these catalysts were fully characterized by low-temperature sorption of N 2 , small-angle and wide-angle XRD, TEM, Raman, XPS, and Py-IR. It was shown that the Nb x W (8 − x) oxides created large amounts of Lewis as well as Brønsted acid sites, which promoted the isomerization of glucose to fructose followed its dehydration to 5-hydroxymethylfurfural (HMF). Mannose was also formed via the epimerization of glucose. Of them, the mesoporous Nb 4 W 4 exhibited the best catalytic activity with a comparatively low E a about 90.2 kJ/mol and good stability in aqueous medium. The kinetic behavior revealed that Lewis acid sites facilitated to glucose-to-fructose isomerization while Brønsted acid sites promoted the dehydration of fructose to form HMF.
研究领域:
催化化学
·
生物质转化
·
绿色化学
·
多相催化
·
材料化学
·
碳水化合物化学
✓ 已验证
DOI
高影响因子
POLYMER
·
2017
·
IF 3.684
Wei Yang,Xu Cheng,Haibo Wang,Yuansen Liu,Zongliang Du
Novel waterborne fluorinated polyurethane (WFPU) based on hydroxyl-terminated poly(fluoroalkyl methacrylates) (HTPFMA) was prepared successfully. The microstructures and micro-phase separation of WFPU were evaluated through infrared spectroscopy (FT-IR), X-ray diffraction (XRD), dynamic mechanical analysis (DMA), and scanning electron microscope (SEM). FT-IR revealed that the H-bonded carbonyl in hard domains increased with the increasing of fluorine content, resulting in enhancing the extent of micro-phase separation between hard and soft segments. XRD results indicated that the crystallinity of hard segment was enhanced with the increasing of fluorine content. The direct visual microstructures by SEM showed that the micro-phase separation was more significant when the fluorine content increased. DMA also revealed strengthened micro-phase separation with increasing fluorine content. The studies of mechanical properties confirmed that WFPU based on HTPFMA had outstanding mechanical properties. The effects of fluorine content on the static contact angles, surface free energy , and surface composition were also studied. The static contact angles of the WFPU films against water and methylene iodide reached around 108° and 84°, respectively. X-ray photoelectron spectroscopy (XPS) confirmed that the fluorine surface enrichment factor in the outermost 10 nm depth was about 10–18 fold higher than its bulk level.
研究领域:
高分子材料科学
·
表面科学
·
材料化学
·
软物质物理
·
功能涂层材料
✓ 已验证
DOI
高影响因子
Nanoscale
·
2015
·Vol. 8
·期 5
·2811-2818
·
IF 7.394
Jia-Mei Yang,Feng-Xia Wang,Ge-Bo Pan
Blend films with long nanowires of zinc octaethylporphyrin (ZnOEP) embedded in an insulating polymer of poly(methyl methacrylate) (PMMA) have been successfully fabricated by a one-step spin-coating process. Concerning photoactive blends based on small-molecule semiconductors, this is quite a novel strategy and allows us to greatly reduce the issues related to low device performance, such as phase-separation, poor connectivity of the semiconducting layer, and higher densities of interfacial defects. Intensive studies on the correlation between the film morphology and device performance have revealed that excellent photodetector performance is derived from efficient charge transport and good connectivity observed in highly crystalline, interconnected ZnOEP nanowires embedded in an insulating PMMA matrix. To the best of our knowledge, this is the first demonstration of a blend-film-based organic photodetector, which exhibits high sensitivity, high stability, high Ion/Ioff ratio, excellent mechanical flexibility, and a broadband responsivity region extending up to 1050 nm. The unique characteristics of facile fabrication, high sensitivity, excellent mechanical stability, and broadband responsivity can make the blend film of ZnOEP and PMMA promising in large-area flexible photodetectors.
研究领域:
材料科学
·
纳米科技
·
有机电子学
·
光电子学
·
柔性电子器件
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Jianling Huang,ChengWei Liao,Hui Wang,YuJun Zhao,Liuzhang Ouyang,Jiangwen Liu,Min Zhu
Mg-based alloy anodes suffer from severe corrosion in conventional electrolytes (KOH solution) and this substantially obstructs the cycle life, which is a great challenge for using them in the Ni-MH battery. Herein, a high concentration tetramethylammonium hydroxide (TMAH) aqueous electrolyte with a special hydrate structure is explored and enables excellent cycle stability and high capacity for Mg-based alloy anodes. In this electrolyte, the Mg 0.4 Ti 0.1 Ni 0.5 alloy anode delivers a maximum discharge capacity of 466 mAh g −1 , and maintains 210 mAh g −1 after 100 cycles owing to the reduced corrosion rate , which are much better than that in 6 M KOH electrolyte, being 425 mAh g −1 and 69 mAh g −1 , respectively. Furthermore, by in-situ forming Cu coating on the Mg 0.4 Ti 0.1 Ni 0.5 electrode surface during charging process with the adding 0.01 M of Cu(OH) 2 in TMAH electrolyte, the corrosion of the electrode is further suppressed and the reversible capacity can reach 313 mAh g −1 after 100 cycles. The high conducting Cu coating can also increase the rate capability of the electrode by promoting the charge transfer. Thus, using TMAH electrolytes provides a new approach to promote the electrochemical performances of Ni-MH batteries with Mg-based alloy anodes.
研究领域:
材料科学
·
电化学
·
能源存储
·
金属腐蚀与防护
·
功能材料
·
电池技术
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 24
·2207362
·
IF 13.3
Yaqiang Ji,Yuan Zhang,Jiaqi Zhu,Pai Geng,Jonathan E. Halpert,Liang Guo
Flexible pressure sensors play an indispensable role in flexible electronics. Microstructures on flexible electrodes have been proven to be effective in improving the sensitivity of pressure sensors. However, it remains a challenge to develop such microstructured flexible electrodes in a convenient way. Inspired by splashed particles from laser processing, herein, a method for customizing microstructured flexible electrodes by femtosecond laser-activated metal deposition is proposed. It takes advantage of the catalyzing particles scattered during femtosecond laser ablation and is particularly suitable for moldless, maskless, and low-cost fabrication of microstructured metal layers on polydimethylsiloxane (PDMS). Robust bonding at the PDMS/Cu interface is evidenced by the scotch tape test and the duration test over 10 000 bending cycles. Benefiting from the firm interface, the developed flexible capacitive pressure sensor with microstructured electrodes presents several conspicuous features, including a sensitivity (0.22 kPa −1 ) 73 times higher than the one using flat Cu electrodes, ultralow detection limit (<1 Pa), rapid response/recovery time (4.2/5.3 ms), and excellent stability. Moreover, the proposed method, inheriting the merits of laser direct writing, is capable of fabricating a pressure sensor array in a maskless manner for spatial pressure mapping.
研究领域:
生物医学工程
·
柔性电子学
·
微纳加工
·
传感器技术
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2019
·Vol. 57
·期 15
·1653-1663
·
IF 2.591
Bin Li,Yan Shi,Zhifeng Fu
Two kinds of Schiff base, N , N ′-dibenzylidene-1,2-diaminoethane (NDBE) and N , N ′-disalicylidene-1,2-diaminoethane, have been found as efficient organic catalyst for reversible complexation-mediated radical polymerization (RCMP) of methyl methacrylate (MMA) for the first time. The polymerization results show obvious features of “living”/controlled radical polymerization. Well-defined and low-polydispersity polymers ( M w / M n = 1.20–1.40) are obtained in RCMP of MMA catalyzed by Schiff base at mild temperature (65–80°C). Moreover, Schiff base also exhibits a particularly high reactivity for RCMP of MMA with in situ formed alkyl iodide initiator. The polymer molecular weight and its polydispersity ( M w / M n is around 1.20) are well controlled even with high monomer conversion. Notably, when the dosage of azo initiator is same as the dosage of iodine, the polymerization could also be realized in the presence of NDBE. The living feature of synthesized polymer is confirmed through the chain extension experiment. In short, Schiff base is a kind of high-efficient catalyst for RCMP and reverse RCMP of MMA, which can be one of the most powerful and robust techniques for polymer synthesis. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1653–1663
研究领域:
高分子化学
·
聚合物合成
·
催化化学
·
功能材料
·
有机合成方法学
✓ 已验证
DOI
高影响因子