JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2022
·
IF 6.437
Jianwei Zhang,Ling Chen,Liangyou Zhao,Guorui Jin,Weidong He
Nitrogen heterocycles as Nitrogen-rich energetic material has been widely popularized due to their desirable properties like low sensitivities, excellent stability, and lower environmental impact, less erosive and less toxic combustion gases , especially in gun propellant application areas. The focus of this study is on investigating interaction mechanism of 1 H-tetrazole (1 H-TZ) and nitrocellulose (NC) by kinetics methods and TG-DSC-FTIR analysis. The mixture (NC-TZ) between 1 H-TZ and NC was prepared by means of physical blending. DSC experiments indicated that the open and closed environment can generate different and important influence on the chemical reaction between 1 H-TZ and NC. Combined with the change of activation energy , it illustrated that the gas 2 H-tetrazole, the isomer of 1 H-TZ, had a significant influence on the thermal decomposition of NC. In comparison with kinetic models of NC and NC-TZ, it can be found that the addition of 1 H-TZ mainly affected the contribution factor and m value in the first stage. The value of m decreased from 1.00 to 0.15, meanwhile, the contribution factor was decreased from 0.50 to 0.12. It showed that NO 2 , the initial decomposition product of NC, had taken part in the thermal decomposition process of 1 H-TZ. TG-DSC-FTIR experiments indicated that there was a chemical reaction between 2 H-tetrazole and the initial decomposition product of NC, NO 2 , to form CO, N 2 O and HN 3 .
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2019
·
IF 6.669
Yuan Zhang,Liping Kang,Hongmei Li,Xianzhang Huang,Xiaoyu Liu,Lanping Guo,Luqi Huang
The combustion of moxa floss was investigated by thermogravimetric/differential scanning calorimeter (TG/DSC), thermogravimetric/Fourier transform infrared spectroscopy (TG-FTIR) and an infrared radiation spectrum-detecting system. The average mass loss rate at the major stage of combustion was 1.08%/min with a peak at 7.86%/min. Moxa floss burning released the integral heat of 9188 mJ/mg from the temperature of 200 °C to 500 °C. The peak heat flow during char combustion stage was higher than those of other stages. The results indicated the combustion of moxa floss was a mild and slow process, releasing heat continuously and steadily. The infrared radiation spectra of burning moxa stick were in a range of 2.5–13.0 µm and showed double peaks at 3.75 µm and 8.75 µm. Thus, this study provided insight into why moxa floss biomass is the optimal material for thermal therapy and is beneficial for the development of electric thermal stimulation alternative.
研究领域:
热疗研究
·
生物医学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2024
·
IF 5.9
Yinhai Pan,Du Wei,Shuo Yao,Haijun Zhang,Quanzhi Tian
Coal gasification slag (CGS) is rich in Li and Ga. However, few studies have focused on the extraction of Li and Ga from CGS. In the present study, the leaching of Li and Ga from CGS calcined with the alkali reagents including NaOH, KOH, Na 2 O 2 , Na 2 CO 3 and K 2 CO 3 were studied through water leaching and solid characterizations including XRD, TG-DSC and NMR. The best leaching percentages of Li and Ga from NaOH-, KOH-, Na 2 O 2 -, Na 2 CO 3 - and K 2 CO 3 -roasted products were 40.81% and 47.89%, 41.19% and 31.60%, 28.04% and 52.40%, 28.21% and 48.58%, and 34.29% and 38.61%, respectively, showing Li and Ga are difficult to be leached out. It has been proven that the formation of insoluble crystal substances (such as NaAlSiO 4 ) in alkali fusion products inhibits the leaching of Li and Ga. In addition, Li and Ga can be released from the insoluble crystal substances due to Na 2 SiO 3 in alkali fusion products can promote the dissolution of insoluble crystal substances into SiO 4 and AlO 4 species, which can improve the leaching of Li and Ga. However, part of the released Li and Ga are stabled in the structure of amorphous substances generated by SiO 4 and AlO 4 species in the form of isomorphism, reducing the leaching of Li and Ga. Thus, this work would provide guidance for the leaching of Li and Ga from CGS.
研究领域:
化学工程
·
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
THERMOCHIMICA ACTA
·
2023
·
IF 3.5
Yongchen Zhu,Jianwei Zhang,Weidong He
5-Amino-1H-tetrazole (5-ATZ), an environmentally friendly energy-containing material for new propellants, is gradually applied in high-energy propellants and its ionic salt compounds have received wide attention. This study focused on investigating the interaction mechanism of guanidinium-5-aminotetrazole (GA) and nitrocellulose (NC) by kinetic methods and TG-DSC-FTIR analysis. DSC and TG experiments indicated that there was a certain interaction during the pyrolysis process of NC and GA. Comparing the kinetic models of NC and peak 3 in NC-GA, it can be found that the addition of GA mainly affected the m-value and contribution in the second step B→C, and the mechanism function changed from F n to C n,m. TG-DSC-FTIR experiments indicated that the initial decomposition product of NC, NO 2 , participated in the thermal decomposition process of GA, and the two reacted chemically to form CO, N 2 O, which made NO 2 unable to completely oxidize the skeleton of NC to produce CH 2 O, HCOOH.
研究领域:
化学
·
材料科学
·
能源与推进剂研究
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2020
·Vol. 10
·期 3
·331
·
IF 3.52
Ergang Yao,Siyu Xu,Fengqi Zhao,Taizhong Huang,Haijian Li,Ningning Zhao,Jianhua Yi,Yanjing Yang,Changjian Wang
The fiber-like bis-(dimethylglyoximato) nickel(II) complex, Ni(DMG)2was successfully synthesized. The obtained samples were characterized by SEM-EDS, FT-IR, XRD, and XPS. The TG-DSC-FTIR-MS coupling technique was used to characterize the thermal decomposition behavior and evolved gas analysis of Ni(DMG)2. The non-isothermal decomposition reaction kinetic parameters were obtained by both combined kinetic analysis and isoconversional Vyazovkin methods. It was found that Ni(DMG)2begins to decompose at around 280 °C, and a sharp exothermic peak is observed in the DSC curve at about 308.2 °C at a heating rate of 10 °C·min−1. The main gaseous products are H2O, NH3, N2O, CO, and HCN, and the content of H2O is significantly higher than that of the others. The activation energy obtained by the combined kinetic analysis method is 170.61 ± 0.65 kJ·mol−1. The decomposition process can be described by the random nucleation and growth of the nuclei model. However, it was challenging to attempt to evaluate the reaction mechanism precisely by one ideal kinetic model.Keywords:nickel (II) complex;dimethylglyoxime;thermal behavior;kinetic analysis;combustion catalyst
研究领域:
材料科学
·
化学动力学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Shiyao Lu,Jian Zhang,Hao Meng,Xiaoyuan Qin,Jianbin Huang,Yehao Liang,Feng-Shou Xiao
Dehydration of methyl lactate (ML) obtained from biomass is a sustainable route for the production of methyl acrylate (MA). Herein, we demonstrate that cesium-exchanged Al-rich Beta zeolite (Cs-Beta) is highly efficient for the dehydration of ML to MA, exhibiting full ML conversion with 87.4% MA yield at 340 °C. In situ FT-IR spectra and kinetic studies provide evidence that the ML dehydration on the Cs-Beta zeolite follows a forward ion-exchange/dehydration/reverse ion-exchange reaction pathway. Model experiments, DFT calculations, TG-DSC analysis, and FT-IR spectra showed that coke formation competes with the dehydration of ML to MA. Kinetic studies and theoretical simulations demonstrate that cesium cations in the micropores of Beta zeolite have a strong steric hindrance, suppressing the formation of oligomers and coke. These results offer new insights for developing highly selective and stable catalysts for the dehydration of ML to MA in the future.
研究领域:
化学工程
·
催化
·
材料科学
·
可持续化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Kang Xue,Huaiyu Li,Lun Pan,Yiran Liu,Xiangwen Zhang,Ji-Jun Zou
With the continuous development of advanced fuel and engine technology, the boundary between liquid and solid fuel is more and more blurred, so the development of new solid-liquid two-phase fuels has become a major opportunity and challenge. Herein, two kinds of [email protected] energetic particles ( [email protected] and [email protected] ) were fabricated by an in-situ electrostatic self-assembly method. The thermal property, ignition and combustion performances of [email protected] are characterized by TG-DSC, CO 2 laser ignition and constant-volume combustion experiments. The results show that the initial exothermic temperature of [email protected] and [email protected] are reduced by about 60 and 110 °C, respectively, compared with nAl (579.6 °C). Moreover, [email protected] has a lower ignition delay time, higher peak pressure, and faster pressurization rate than nAl, especially [email protected] and [email protected] The combustion process of [email protected] is proposed, which can be obviously enhanced by regulating the interfacial reaction and the generation of microexplosions. In the ignition experiment of nanofluid fuel, [email protected] energetic particles exhibit the bifunction characteristics, which can simultaneously improve the ignition and combustion performances of solid-phase nAl particles and liquid-phase hydrocarbon fuel. This work provides a new strategy for advanced aerospace fuel by introducing MOF shells to construct bifunctional energetic particles with enhanced ignition and combustion properties.
研究领域:
材料科学
·
化学工程
·
航空航天工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Zeshuai Li,Feifei Zhou,Baosheng Xu,Donghui Guo
We present a simple way to fabricate high-entropy (La 0.2 Nd 0.2 Sm 0.2 Dy 0.2 Yb 0.2 ) 2 Zr 2 O 7 (HE-RE 2 Zr 2 O 7 ) ceramic nanofibers using the electrospinning and annealing processing in this work. The microstructure of nanofibers was characterized by thermal gravity-differential scanning calorimetry (TG-DSC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. Meanwhile, the diameter and grain growth of HE-RE 2 Zr 2 O 7 nanofibers under 1000 °C was analyzed. Results indicate that HE-RE 2 Zr 2 O 7 nanofibers can be prepared at temperatures above 400 °C and the crystallite size can be controlled by annealing temperature. Both diameter and the grain growth of HE-RE 2 Zr 2 O 7 nanofibers are lower than that of La 2 Zr 2 O 7 nanofibers, attributed to the sluggish diffusion effect. The advantages of HE-RE 2 Zr 2 O 7 nanofibers can further enlarge the application of nanofibers in the aspect of high-temperature thermal insulation materials.
研究领域:
材料科学
·
陶瓷
·
纳米技术
·
隔热材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Hongju Qiu,Weiwei Huang,Yanqiong Zhang,Jin Chen,Lei Gao,Mamdouh Omran,Li Nan,Guo Chen
In the family of inorganic nanomaterials , zirconia is a highly promising functional ceramic with a high refractive index , hardness, and dielectric constant, as well as excellent chemical inertness and thermal stability. These properties are enhanced in nano-zirconia ceramics, because nanopowders have a small particle size, good morphology, and uniform and dispersive distribution. In this study, a co-precipitation process was proposed to synthesise highly dispersed MgO–Y 2 O 3 co-stabilized ZrO 2 nanopowders. The effects of different calcination temperatures on the crystallisation degree and particle dispersion of zirconia nanopowders were characterised by X-ray diffraction (XRD), thermogravimetry-differential scanning calorimetry (TG-DSC), Raman spectroscopy , Fourier transform infrared spectroscopy (FTIR), nitrogen adsorption using the Brunauer–Emmett–Teller (BET) theory, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FESEM). The optimum synthesis conditions were obtained as follows: 6 h of high-energy planetary grinding and calcination at 800 °C in an electric furnace. Under these optimum conditions, the average particle size of the prepared powder was 28.7 nm. This process enriches the literature on the controllable preparation of Mg–Y/ZrO 2 nanopowders obtained by the co-precipitation method.
研究领域:
材料科学
·
纳米技术
·
陶瓷工程
·
化学工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2022
·
IF 8.025
Peng Zhou,Xiangzhou Li,Zhi Jiang,Jun Zhou,Guang He,Limin Qu
In this paper, a kind of superabsorbent resin (SAR) with superior quality for hygiene products was developed using Fructus Aurantii Immaturus pectin (FAIP) from Citrus aurantium L.. FAIP-g-AM/AMPS SAR was established by free radical graft co -polymerization with FAIP as skeleton structure, N, N′-Methylene-bis (acrylamide) (MBA) as the cross-linker. Meanwhile, the functional monomers of acrylamide (AM) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) were introduced. The structure and morphology of FAIP-g-AM/AMPS were characterized by FTIR , 13 C NMR, XRD, SEM and TG-DSC analysis. The results confirmed that the AFIP-g-AM/AMPS SAR was successfully prepared, which exhibited a three-dimensional (3D) network structure and an excellent thermal stability . The absorption and retention capacity of FAIP-g-AM/AMPS was comparable to or even better than commercial diapers and sanitary napkins. Significantly, FAIP-g-AM/AMPS itself exhibited excellent antibacterial and safety. FAIP-g-AM/AMPS has an inhibition ratio of 97.1 % for Escherichia coli ( E. coli ) and 98.5 % for Staphylococcus aureus ( S. aureus ), and was non-irritating and non-allergic to the skin. In addition, FAIP-g-AM/AMPS presented amazing biodegradability and a weight loss reached 37.1 % after 30 days by soil burial test. The research provides a safe and high-performance SAR, which expected to be used in hygiene products such as baby diapers, adult incontinence pads and sanitary napkins.
研究领域:
材料科学
·
高分子化学
·
生物技术
·
环境科学
·
卫生用品
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）