Defence Technology
·
2018
·
IF 0
Teng Chen,Yan Zhang,Shuang-feng Guo,Liu-ming Zhao,Wei Chen,Ga-zi Hao,Lei Xiao,Xiang Ke,Wei Jiang
A sol-gel freezing-drying method was utilized to prepare energetic nanocomposites based on 2, 4, 6, 8, 10, 12-hexanitro-2, 4, 6, 8, 10, 12-hexaazaisowurtzitane (CL-20) with 3, 3-Bis (azidomethyl) oxetane-tetrahydrofuran copolymer (BAMO-THF) as energetic gel matrix. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman, Fourier-transform infrared spectroscopy (FT-IR) and differential thermal analyser (DTA) were utilized to characterize the structure and property of the resultant energetic nanocomposites. Compared with raw CL-20, the average particle sizes of CL-20 in CL-20/BAMO-THF energetic nanocomposites were decreased to nano scale and the morphologies of CL-20 were also changed from prismatic to spherical. FT-IR detection revealed that CL-20 particles were recrystallized in BAMO-THF gel matrix during the freezing-drying process. The thermal decomposition behaviors of the energetic nanocomposites were investigated as well. The thermolysis process of CL-20/BAMO-THF nanocomposites was enhanced and the activation energy was lower compared with that of raw CL-20, indicating that CL-20/BAMO-THF nanocomposites showed high thermolysis activity. The impact sensitivity tests indicated that CL-20/BAMO-THF energetic nanocomposites presented low sensitivity performance.
研究领域:
材料科学
·
爆炸物化学
✓ 已验证
产品关联
DOI
Journal of Energetic Materials
·
2018
·
IF 2.183
Teng Chen,Wanhui Li,Wei Jiang,GaZi Hao,Lei Xiao,Xiang Ke,Jie Liu,Han Gao
Novel 1,3,5-trinitro-1,3,5-triazine/3,3-bis (azidomethyl) oxetane-tetrahydrofuran copolymer (RDX/BAMO-THF) energetic nanocomposites were successfully prepared by a facile sol–gel freezing–drying method. The as-prepared RDX/BAMO-THF energetic nanocomposites were characterized by Raman and Fourier transform infrared spectroscopy, which revealed that RDX particles were incorporated into BAMO-THF gel matrix. Scanning electron microscopy was used to characterize the morphology and the particle size of the as-obtained samples. The results showed that RDX particles were trapped in the BAMO-THF gel matrix and the particle sizes were in nanoscale. Differential thermal analyzer (DTA) was performed to determine the thermal decomposition behaviors of BAMO-THF, raw RDX and RDX/BAMO-THF nanocomposites. The results indicated that the thermal decomposition process of RDX/BAMO-THF nanocomposites was enhanced compared with that of BAMO-THF and RDX. The kinetic, thermodynamic and thermal stability parameters were calculated according to DTA analysis. The calculated results revealed that RDX/BAMO-THF nanocomposites presented high thermal reactivity. The results of impact sensitivities for RDX/BAMO-THF nanocomposites indicated the sensitivity was effectively reduced compared to raw RDX.
研究领域:
材料科学
·
化学工程
·
爆炸物科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2020
·
IF 5.578
Xibin Wang,Rixin Chen,Benzhuang He,Dehua Li,Mingyuan Qin,Xiangshan Fan
Laminar flame characteristics of THF family fuels, including tetrahydrofuran (THF), 2-methyltetrahydrofuran (MTHF) and 2,5-dimethyltetrahydrofuran (DMTHF), were studied in constant volume bomb using high-speed schlieren photography technique under the conditions of initial pressure of 1–4 bar, initial temperature of 373–453 K and equivalence ratio of 0.7–1.6. The nonlinear extrapolation method was used to obtain the laminar burning velocity and Markstein length. The results showed that laminar burning velocities of the three fuels vary with equivalence ratio and reached their peak value at equivalence ratio near 1.1, and are accelerated with the elevated initial temperature and decelerated with the elevated initial pressure. The relationship of laminar burning velocity among the three fuels is THF > MTHF > DMTHF. The difference of the velocity is mainly due to the adiabatic flame temperatures and thermal diffusivity which are THF > MTHF > DMTHF and THF≈MTHF > DMTHF respectively. Quantitative analysis indicates that the laminar burning velocity is positive exponential power function with initial temperature and negative exponential power function with initial pressure. The laminar burning velocities of the three fuels are more sensitive to the variation of both initial temperature and pressure for fuel-lean mixtures, and MTHF is the most sensitive among the three fuels. Flame instability among the three fuels is THF≈MTHF > DMTHF, because the relationship of the effective Lewis number and flame thickness is THF < MTHF < DMTHF, meaning that the diffusion-thermal instability among the three fuels is THF > MTHF > DMTHF.
研究领域:
燃烧学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Yaning Kong,Fei Wang,Guodong Zhang,Xiaolin Wang
It is anticipated to achieve safe, economical, and high-density hydrogen storage via hydrate, but sluggish formation kinetics of H 2 hydrate and low hydrogen storage capacity limit its application, and appropriate kinetic promoters are required to improve the situation. In this work, three nano promoters were prepared by soap-free emulsion polymerization method, the functional groups of -SO 3 − , –COO − and -N(CH 3 ) 3 + were separately immobilized on nano spheres to produce the nano promoters of -SO 3 − @PSNS, –COO − @PSNS and -N(CH 3 ) 3 + @PSNS, and their influence on the formation kinetics of mixed H 2 /THF hydrate was evaluated, while the performance of conventional kinetic promoters of methane hydrate was also estimated for comparison. It was found that the formation kinetics of mixed H 2 /THF hydrate was enhanced in the presence of nano promoters, which improve early growth of H 2 /THF hydrate and later water-to-hydrate conversion, leading to large hydrogen storage capacity. -SO 3 − @PSNS causes H 2 /THF hydrate to be looser and performs the best among the three nano promoters, hydrogen storage capacity in -SO 3 − @PSNS system is up to 0.467 wt% at 12 MPa, which increase by 39.8% comparing with that in pure THF system, and satisfactory hydrogen storage capacity of 0.303 wt% was also obtained under milder condition (7 MPa). For conventional kinetic promoters, L-methionine performs the best and shows similar promotion effect like -SO 3 − @PSNS, but it is excluded for large-scale industrial application when taking its high cost and perishable nature into consideration, whereas this scenario is improved by the proposed nano promoters.
研究领域:
化学工程
·
能源科学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2021
·
IF 4.291
Jiamin Pan,Jie Ma,Lian Liu,Denghui Li,Yuting Huo,Hui Liu
Based on the known deprotection reaction of thioacetal initiated by Hg 2+ , a new type of fluorescent probe 3-(4-(1,3-dithiolan-2-yl) phenyl)-9H-carbazole (DTCB) is designed and synthesized successfully. The probe shows a good fluorescence response to Hg 2+ in THF-H 2 O ( f w = 5%) mixed system. The addition of Hg 2+ greatly enhances the fluorescence intensity of the probe and changed from dark blue to green fluorescence. Within a large Hg 2+ concentration range (0–6×10 −5 mol·L −1 ), the fluorescence intensity at 480nm presents good linear with the Hg 2+ concentration (R 2 = 0.993), and the detection limit of the probe to Hg 2+ is below 2.05×10 −7 mol·L −1 . The DTCB probe shows good selectivity and anti-interference performance, and many metal ions and anions hardly effect on its detection performance. The sensing mechanism is confirmed by theory calculation based on DFT and TD-DFT theories, and the intramolecular charge transfer (ICT) is responsible for the significant fluorescence change of probe DTCB. Meanwhile, the probe is applied to the detection of Hg 2+ in real water samples; and it is interesting that the DTCB-based test strip firstly reveals the strong fluorescence from solid-state 3-(4-formylphenyl)-9H-carbazole (FCB) with Hg 2+ adding. The results show that the probe based on DTCB has potential application prospect in actual sample analysis.
研究领域:
分析化学
·
环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Jibao Zhang,Yan Li,Zhenyuan Yin,Praveen Linga,Tianbiao He,Xiang Yuan Zheng
Hydrogen (H 2 ) emerges as a promising future clean energy for the low-carbon and sustainable future due to its high energy density and no pollutant or greenhouse gas emissions after combustion. The advantage of H 2 storage in solid-hydrate form is the requirement of only moderate pressure and temperature compared to compressed H 2 storage and the relatively lower energy consumption compared to liquid H 2 storage. However, the slow kinetics of H 2 hydrate formation is one major challenge to breakthrough for the large-scale development of hydrate-based H 2 storage. In this study, we introduced an environmental-benign kinetic promoter ( L -valine, L -Val) and coupled it with a thermodynamic promoter tetrahydrofuran (THF) using stoichiometric concentration (5.56 mol%) to enhance H 2 hydrate formation kinetics. 0.3 wt% L -Val coupled with 5.56 mol% THF yields the optimal kinetic enhancement, and the maximum volumetric H 2 uptake ( V H2 ) is 29.83 ± 1.22 volume of H 2 /volume of H 2 -THF hydrate (v /v). The reusability of L -Val is proved in five consecutive cycles of H 2 -THF hydrate formation and dissociation with consistently superior H 2 uptake. Furthermore, it was identified that cooling rate ( R c ) was an important factor determining the H 2 -THF hydrate formation kinetics. Lower R c (0.05 K/min) shows an optimal promoting effect of V H2 , which was 105.29% higher than that at higher R c (0.3 K/min). A mechanism is proposed to explain the effect of R c on H 2 -THF hydrate formation kinetics. The maximum gravimetric H 2 ( G H2 ) reported in our study reaches 0.26 ± 0.01 wt%, which was superior in current literature below 15.0 MPa. The results provide insights into speeding up H 2 uptake in solid-hydrate form and have potential applications in hydrate-based hydrogen storage.
研究领域:
化学工程
·
能源存储
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Xuejian Liu,Yan Li,Guang-Jin Chen,Dao-Yi Chen,Bo Sun,Zhenyuan Yin
CO2 capture and sequestration are broadly recognized as the most effective technology for reducing CO2 emissions and mitigating global climate change. In this regard, hydrate-based CO2 sequestration (HBCS) has been proposed as an effective method for long-term safe and stable CO2 sequestration. It is a promising technology for reducing the concentration of CO2 in the atmosphere and achieving carbon neutrality. However, one major challenge related to HBCS technology is the lack of understanding of how to improve the formation kinetics of CO2 hydrate effectively. Herein, in this study, we identified the synergistic promotion effect on CO2 hydrate formation when a low-dose thermodynamic promoter (tetrahydrofuran, THF) is coupled with an environment-friendly kinetic promoter (l-methionine, l-Met). Based on the kinetic experiments and the morphological observation, 0.6 mol % THF coupled with 0.1 wt %l-Met yields the optimal CO2 gas uptake. In situ Raman spectra reveal the mechanism of the observed two-step growth behavior at the molecular level, where low-dose THF promotes the initial CO2-THF sII hydrate nucleation and growth in the solution and l-Met promotes the subsequent CO2 sI hydrate growth along the surface of the reactor. Our study unveils the underlying synergistic mechanism when thermodynamic and kinetic promoters are coupled for CO2 hydrate formation. The results provide guidance for the identification and use of novel bio-friendly thermodynamic and kinetic promoters and are beneficial to a series of sustainable hydrate-based technologies when fast CO2 formation is required.
研究领域:
化学工程
·
环境科学
·
材料科学
·
可持续能源
✓ 已验证
产品关联
DOI
高影响因子
Energy Storage Materials
·
2022
·
IF 20.831
Yan Han,Gaofeng Li,Zijun Hu,Feng Wang,Jun Chu,Liang Huang,Tingting Shi,Hui Zhan,Zhiping Song
Rechargeable magnesium batteries (RMBs) are regarded as one of the promising candidates of next generation of battery technologies, but seriously hampered by the sluggish kinetics of Mg 2+ -related cathode reactions. A pertinent solution is adding Li salt into the electrolyte to build a hybrid Mg/Li battery (MLB), which combines the high safety of Mg anode and the fast reaction kinetics of Li + with the cathode material . Herein, we propose a novel, simple, and cheap dual-salt electrolyte for MLBs, namely MgCl 2 –LiCl/THF, based on the exceptional synergetic effect between MgCl 2 and LiCl in THF . The 1.0 M electrolyte demonstrated desired ionic conductivity (1.3 mS cm –1 ), good compatibility with Mg anode, and adequate oxidation potential (2.2 V vs. Mg) for typical organic cathode materials including poly(anthraquinonyl sulfide) (PAQS), poly(1,4-anthraquinone) (P14AQ), and dilithium salt of poly(2,5-dihydroxy-p-benzoquinonyl sulfide) (Li 2 PDHBQS). Unlike PAQS and P14AQ adopting MgCl + as inserted cation, Li 2 PDHBQS selected Li + to participate in the reaction. Therefore it demonstrated superior electrochemical performance to most of previously reported inorganic and organic cathode materials for MLBs, including a high reversible capacity (282 mAh g −1 ), a high rate capability (72% @ 2000 mA g −1 ), and a high cycling stability (70% @ 500th cycle). The combination of MgCl 2 –LiCl/THF electrolyte and Li 2 PDHBQS cathode provides not only a successful example of high-performing and affordable MLBs, but also insights of ionic species in the electrolytes and their interactions with organic cathode materials, which are very significant for the further development of RMBs.
研究领域:
储能
·
电化学
·
材料科学
·
电池技术
·
有机电极材料
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2022
·
IF 4.654
Biao Liu,Linsen Zhan,Hailong Lu,Xindi Lu,Wenjiu Cai
The knowledge of the mechanism of clathrate hydrate formation is crucial for studying the formation of a natural gas hydrate and developing hydrate-based technologies. In this study, low-field nuclear magnetic resonance (NMR) is applied to observe the processes of tetrahydrofuran (THF) hydrate formation from the solutions with different THF concentrations, and from the analysis of the NMR transverse relaxation time (T2) of hydrates and solutions, the formation mechanism of THF hydrate is discussed. A quantitative relationship between the NMR T2 spectral area and the mass of THF hydrate is established, and it is applied to estimate the hydrate amount in the formation process of THF hydrate. The results obtained show that T2 of THF solution is controlled by the temperature and THF concentration: longer at a higher temperature and shorter at a higher THF concentration. Moreover, the initial THF concentration does not affect the final concentration of the remaining solution after hydrate crystallization, and the formation of THF hydrate from solution follows the thermodynamics of solution reaction, with the THF concentration of the solution ending at the phase line after hydrate crystallization. The kinetics of THF hydrate formation is affected by the temperature and THF concentration: a higher formation rate in the solution with stoichiometric composition (19.06 wt % THF) of THF hydrate than either THF-rich or water-rich solution and a lower formation rate at a higher temperature.
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Minbo Qi,Hui Huang,Ying Zhang,Haixia Wang,Hanbo Li,Zhenmei Lu
Our understanding of the tetrahydrofuran (THF) degradation in complex environment is limited. The majority of THF degrading genes reported are group V soluble diiron monooxygenases and share greater than 95% homology with one another. In this study, we used sole-carbon-source incubation combined with high-throughput metagenomic sequencing to investigate this contaminant's degradation in environmental samples. We identified as-yet-uncultivated microbe from the genera Pseudonocardia and fungi Scedosporium sp. ( Scedosporium sp. was successfully isolated) as THF degraders as containing THF degradation genes, while microbes from the genera Bordetella , Pandoraea and Rhodanobacter functioned as main cooperators by utilizing acidic intermediates and providing anti-acid mechanisms. Furthermore, a 9387-bp THF degradation cluster designated thmX from the as-yet-uncultivated Pseudonocardia (with 6 main ORFs and with 79–93% amino acid sequence identity with previously reported clusters) was discovered. We also found a THF-degrading related cytochrome P450 monooxygenase from the genus Scedosporium and predicted its cognate reductase for the first time. All the genes and clusters mentioned above were successfully amplified from samples and cloned into the suitable expression vectors. This study will provide novel insights for understanding of THF degradation mechanisms under acid stress conditions and mining new THF degradation genes.
研究领域:
环境科学
·
微生物学
·
基因组学
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2022
·
IF 8.035
Yimao Shen,Zhi Li,Jingtao Hu,Yue Zhang,Tianduo Li,Guangjin Chen
Gas hydrate technology is a new gas storage method developed in recent years and has great application potential. Due to the slow formation kinetics of hydrate and the low actual gas storage density, it is a promising method to prepare the fixed bed filled with wet porous materials to inducing adsorption-hydration coupling effect, so as to improve the gas storage efficiency. In this study, various additives including THF, TBAB and diesel oil were added to the water-bearing activated carbon fixed bed to improve its gas storage capacity. Our experimental results show that the addition of THF or TBAB can significantly promote the gas storage performance of the bed. At the optimum concentration of THF (7.5 wt%), the gas storage density of bed (S b ) and gas storage capacity of hydrate (S w ) were 128.66 V/V b and 194.26 V/V w , which are 2.89 times and 3.07 times higher than those of wet activated carbon fixed bed without additives, respectively. When 5 wt% TBAB was added, the S b and S w were increased by 1.86 times and 1.87 times, respectively. Moreover, using diesel to establish gas channels in the fixed bed to improve the gas mass transfer between the bulk gas phase and the fixed bed can also significantly improve the gas storage performance of the bed. When the oil-carbon ratio (R o ) is 0.5, the S b and S w are 97.97 V/V b and 172.77 V/V w , respectively. However, further increasing the amount of diesel oil will not significantly improve the gas storage density of the bed due to the volume increase of the bed caused by the addition of diesel. When both diesel oil and THF are added to the water-containing fixed bed, the effect will be not significantly better than that of the bed with diesel oil or THF alone because the two accelerators compete with each other. Finally, the gas release and decomposition speed of the water-bearing fixed bed with / without 7.5 wt%THF are investigated. The results show that the final gas recovery of the bed with 7.5 wt% THF could reach 95.01 %, indicating a good application prospect.
研究领域:
化学工程
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2013
·Vol. 31
·期 3
·393-400
·
IF 0.917
Anna Zheng,Bo Chen,Dihang Hu,Yong Guan,Dafu Wei,Shuzhao Li,Dandan Ji
This work confirms the new view of the initiation and propagation mechanism of the anionic polymerization previously proposed, based on the investigation of anionic bulk-polymerization of styrene and α -methyl styrene with the help of a self designed microflow device and characterized by GPC and in situ 7 Li NMR. It was found that n -BuLi tended to form the hexameric-aggregated structure and even to form the huge aggregated structure based on the former. These aggregations of initiators could directly initiate the anionic polymerization and form the supramolecule aggregations. The supramolecule aggregations inevitably blocked the diffusion of the monomers to the ion-pairs and resulted in a stationary-conversion platform. Then the aggregators were dissociated completely into equal binary-aggregated species, and the polymerization continued again rapidly before the termination. Tetrahydrofuran (THF) acted as the electron donator, which could push the electron cloud to Li cation and make the aggregated ring of the active species rather loosened and facilitated the monomer to insert in. Therefore, a little THF can greatly promote the anionic polymerization. However, further addition of THF might block the channel between the ion-pairs and decrease the propagation rate. It was also found that the aggregated structure of the active species during the anionic polymerization only depends on the initiator aggregations which were formed before the polymerization.
研究领域:
化学
·
高分子科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）