RENEWABLE ENERGY
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2023
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IF 8.7
Yun Zhang,Chuanbiao Zhang,Wenjuan Li,Qiuping Xiao,Fengyuan Jiao,Sen Xu,Yanhua Lan,Yizheng Fu,Chi-Min Shu,Weiguo Cao
Stearic acid provides a basis for developing renewable energy, such as solar energy and biomass energy. A thermogravimetric-infrared spectroscopy (TG-IR) experimental test is conducted to obtain the thermal decomposition progress and the main gaseous products of stearic acid. The result shows that small gaseous products (H 2 O, CO 2 , CO, alkanes, olefins , etc.) are released. Furthermore, the method of reactive molecular dynamics simulation (ReaxFF-MD) is utilized to look into the pyrolysis reaction mechanism of stearic acid. The main pyrolysis products of stearic acid received by ReaxFF-MD are C 2 H 4 , H 2 , C 2 H 2 , CH 4 , H 2 O, CO 2 , and CO, consisting of the result of the TG-IR test. The effect of the simulated system density and temperature on the distribution of main products is also explored. Also, the thermal kinetic analysis is conducted by the initial consumption of stearic acid under different temperatures. The primary reaction mechanism of stearic acid pyrolysis is that the stearic acid molecules dissociate through C–C bonds break to generate C 2 H 4 , CH 4 , C 2 H 2 , C 3 H 6 , and other small molecules and radicals, and a typical reaction mechanism scheme of stearic acid pyrolysis is presented. The results provide a reference for explaining the macroscopic explosion characteristics of dust at the microscopic mechanism level.
研究领域:
化学工程
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2025
·
IF 11.3
Hailan Wang,Ruobin Dai,Zhiwei Wang
Deciphering the structure and composition of the scaling layer is crucial for understanding its formation mechanisms in the reverse osmosis (RO) process. However, conventional characterization techniques face challenges in providing high three-dimensional resolution and precise compositional analysis of mixed scales, which hinders in-depth elucidation of the underlying mechanisms. In this study, we combined the exceptional depth resolution of time-of-flight secondary ion mass spectrometry (ToF-SIMS) and the superior mixed-scale discrimination capability of thermogravimetry-infrared spectroscopy (TG-IR) to analyze Si/Al scaling, a common issue in industrial RO systems. Under acid conditions, ToF-SIMS measurements revealed Al species enrichment on the membrane surface, attributed to the strong affinity between Al3+ and the membrane. The preferential deposition of Al3+ further facilitated the heterogeneous nucleation of polymerized silica through the electrostatic shielding effect, leading to the rapid formation of a thin and dense scaling layer. In contrast, neutral and alkaline conditions produced a slower-developing, uniform, thicker, and loosely structured scaling layer through physical deposition of supersaturated Si/Al complex scales. TG-IR analysis revealed that neutral conditions favored coprecipitated adsorption-bound Si/Al species (6-coordinate Al) and Si/Al polymers (4-coordinate Al), whereas alkaline conditions primarily produced coprecipitated silica and Al(OH)4−. These findings advance the mechanistic understanding of Si/Al scaling and provide a foundation for targeted control strategies in silica-metal combined scaling in RO systems.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 138
·期 46
·51364
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IF 3.125
Huimin Zhang,Dan Meng,Wenjia Wang,Hongfei Li,Xiaoyu Gu,Sheng Zhang,Jun Sun,Fei Xin,Zuodong Qin,Wufei Tang
A modified kaolinite by grafting with phytic acid (PA-g-Kaol) is fabricated, and it was introduced into ethylene vinyl acetate (EVA) with intumescent flame retardancy (IFR) together to improve the flame retardancy of EVA composites. The results show the limiting oxygen index value of EVA/ (18.0 wt% IFR)/ (2.0 wt% PA-g-Kaol) is 30.8%. Meanwhile, there is only one dripping produced in the vertical burning test. What's more, the flame-retardant mechanism is demonstrated by TG-IR, real-time-IR and GC–MS analysis. The results indicate that some pyrolytic products of IFR and PA-g-Kaol, like ammonia and phosphoric acid, catalyze the crosslinking of EVA and flame retardant, the resultant compact char protects the substrate from further burning.
研究领域:
材料科学
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聚合物化学
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消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2020
·
IF 4.032
Zhiyuan Chi,Zongwei Guo,Zice Xu,Mengjie Zhang,Ming Li,Lei Shang,Yuhui Ao
Searching a renewable and flame-retardant alternative to bisphenol A epoxy resins is a necessary development trend. Diphenolic acid , a plant derivative, has been proven to be one of the sustainable alternatives to bisphenol A. However, how to impart the flame-retardant property to diphenolic acid thermosets is still a challenge to synthesize high performance intrinsic flame-retardant bio-based epoxy resins. A flame-retardant bio-based epoxy resin (TEBA) was designed and synthesized via a three-step synthetic pathway from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)、diethanolamine and diphenolic acid (DPA). The chemical structures of the intermediate and final products were confirmed by 1 HNMR and FTIR spectroscopy. TEBA cured with 4,4′-diaminodiphenylmethane (DDM) curing agent was compared with a standard bisphenol A epoxy resin (DGEBA). Due to the combination of phosphorus and nitrogen in the main chain, the TEBA-DDM shows superior flame retardancy. Compared with DGEBA-DDM, LOI of TEBA-DDM increased from 25.8% to 42.3%, UL-94 test rating from no rating to V-0 rating, self-extinguishing within 3s. The peak heat release rate (PHRR) in the cone calorimetry test decreased by 67%. total heat release (THR) and total smoke generation (TSP) decreased by 27% and 35%, respectively. In addition, the flame retardant mechanism of TEBA epoxy thermosets was researched by FTIR, residual char photograph, SEM, TG-IR analysis and Raman spectroscopy . Meanwhile, TEBA-DDM and DGEBA-DDM have comparable mechanical properties .
研究领域:
材料科学
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化学工程
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高分子科学
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可持续化学
✓ 已验证
产品关联
DOI
高影响因子
FIRE SAFETY JOURNAL
·
2025
·
IF 3.3
Haoran Jiang,Yong Hu,Yong Jiang,Rong Qiu,Hui Huang
Due to the increased risk of phosphate depletion, there is an increasing demand for low-phosphorus or bio-based phosphorus flame inhibitors. Therefore, two novel composites with biologically-based phosphorus sources that chelate transition metal ions were synthesized via assembly method, i.e., Mn-PMC and Ni-PMC, the structure and binding states of the composites were examined by SEM, TEM, FTIR, XRD, XPS, BET and TGA. The results indicated that Mn-PMC and Ni-PMC (ⅰ) are nanoscale materials with well dispersed, (ⅱ) have an amorphous structure and have sites that bind to other substances, (ⅲ) contain no halogen elements. Then the combustion inhibition experiments of downward flame spread and TG-IR-MS analysis revealed (ⅰ) that the inhibition efficiency of the two prepared inhibitors was higher than that of commercial phosphate-containing inhibitor ADP. Among them, Ni-PMC had the best suppression effect, and the flame of cellulose sample containing it would automatically extinguish after igniting with a smallest dosage, (ⅱ) two inhibitors reduced the laminar flame velocity and flame temperature. (ⅲ) their flame suppression mechanism was indicated as that the pyrolysis releases inert gas to dilute the free radical concentration. This work is helpful for the development of efficient transition metal fire extinguishing agents to replace traditional phosphorus resources.
研究领域:
材料科学
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燃烧学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2020
·Vol. 7
·期 20
·2001681
·
IF 15.84
Daping Qiu,Jingyu Guan,Min Li,Cuihua Kang,Jinying Wei,Feng Wang,Ru Yang
Potassium-ion hybrid capacitors (PIHCs) have attracted tremendous attention because their energy density is comparable to that of lithium-ion batteries, whose power density and cyclability are similar to those of supercapacitors. Herein, a pomegranate-like graphene-confined cucurbit[6]uril-derived nitrogen-doped carbon (CBC@G) with ultra-high nitrogen-doping level (15.5 at%) and unique supermesopore-macropores interconnected graphene network is synthesized. The carbonization mechanism of cucurbit[6]uril is verified by an in situ TG-IR technology. In a K half-cell configuration, CBC@G anode demonstrates a superior reversible capacity (349.1 mA h g −1 at 0.1 C) as well as outstanding rate capability and cyclability. Moreover, systematic in situ/ex situ characterizations, and theory calculations are carried out to reveal the origin of the superior electrochemical performances of CBC@G. Consequently, PIHCs constructed with CBC@G anode and KOH-activated cucurbit[6]uril-derived nitrogen-doped carbon cathode demonstrate ultra-high energy/power density (172 Wh kg −1 /22 kW kg −1 ) and extraordinary cyclability (81.5% capacity retention for 5000 cycles at 5 A g −1 ). This work opens up a new application field for cucurbit[6]uril and provides an alternative avenue for the exploitation of high-performance PIHCs.
研究领域:
材料科学
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电化学
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能源存储
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）