MATERIALS RESEARCH BULLETIN
·
2017
·
IF 2.446
S.T. Zhang,Y.R. Ruan,C. Liu,P. Wang,Y.Q. Ma
α-Fe/FeTiO 3 /TiO 2 was synthesized through the reduction of Fe 3 O 4 @TiO 2 at 800 °C, and subsequently nitrided in NH 3 atmosphere at the nitridation temperature T N = 400, 600, 800 and 1000 °C. In the crystal lattice of TiO 2 , with increasing T N , the N element itself exhibits the chemical states of TiO 2-x N x , TiN and interstitial N, and simultaneously it induces the complex variation of the chemical state of the Ti and O elements. The photocatalytic performance of the nitrided samples is not determined only by the chemical states of the N element but by the synergistic effects of chemical states of the N, Ti and O elements.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2023
·
IF 5.9
Ying-Ming Li,Wen-Juan Hu,Shuang-Lin Hu,Yi-Ran Li,Dan-Ping Zhu,De-Yi Wang
The rigid polyurethane foam (RPUF) with excellent flame retardancy, high compressive strength and good thermal insulation performance is of great importance to its widely application, especially the application in high-rise building exterior wall materials. In this work, two kinds of flame-retarding polyols (DADP and APDP) containing phosphorus and nitrogen elements were prepared via a simple salinization reaction and reacted into RPUF chains. When only 15 wt% of APDP was incorporated, the material passed the UL-94 V-0 rating with a limiting oxygen index (LOI) of 24.5% while 20 wt% of DADP incorporated to realize the same flame-retarding effect. For the RPUF/APDP 15 , the peak heat release rate (PHRR) decreased by 28.2% comparing to the neat RPUF and the fire growth rate (FIGRA) was the lowest 8.3, indicating the lowest flame spread speed among all the flame-retarding RPUF. The compressive strength of the RPUF/APDP 15 material increased by 41.8% comparing to that of neat RPUF, mainly causing by the good compatibility and the enhancement of hardness of polyurethane via the benzene ring. Moreover, it was concluded that the gas-phase mechanism dominated in enhancing the flame-retarding effect for the RPUF material, and the APDP showed a higher flame-retarding effect with a higher content of phosphorus and nitrogen elements than that of DADP.
研究领域:
材料科学
·
防火材料
·
建筑保温材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 48
·45556
·
IF 1.86
Hongqiang Yan,Li Zhao,Zhengping Fang,Hao Wang
Complex multilayer coatings composed of α-zirconium phosphate (ZrP), polyethylenimine (PEI), and ammonium polyphosphate (APP) were constructed via layer-by-layer assembly method for flame retardant ramie fabric. Bicomponent PEI/ZrP layers served as insulating barrier coating, and bicomponent PEI/APP layers served as intumescent coating. The flame retardancy of the coated ramie fabric was strongly dependent on the nature of the coatings and the layer-by-layer assembly patterns. The coated ramie fabric with inside PEI/ZrP layers and outside PEI/APP layers possessed the most uniform and consistent coating surface morphology, as well as the highest content of N and P elements, resulting in an excellent improvement in flame retardancy of ramie fabrics. When this kind of coated ramie fabric was heated, the inner PEI/ZrP layer effectively prevent oxygen and heat from penetrating into the substrate, and the outer PEI/APP layer exposed to air with good expansion during combustion. The synergistic effect was formed during the combustion process and could impart ramie fabrics with high flame retardancy. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45556.
研究领域:
材料科学
·
纺织工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Dong Wang,Junshuang Zhou,Junkai Li,Yuanzhe Wang,Li Hou,Faming Gao
Because of its high density, a carbon microsphere is a good candidate for ultrahigh volumetric capacity electrode materials. We find that the synergistic effects of nitrogen and iodine element can tremendously improve the carbon electrode capacity. Here, we present a high volumetric capacity anode consisting of iodine and nitrogen codoping carbon microspheres synthesized by a low-temperature solvothermal route. A reversible capacity of 1418 mAh cm–3, which is much larger than that of commercial graphitic carbon anode, is achieved at a current density of 0.05 mA cm–2 by using these carbon microspheres as anode material. After 100 charge–discharge cycles at 0.1 mA cm–2 and 500 charge–discharge cycles at 1 mA cm–2, carbon microspheres retained volumetric capacities of 1335 and 1090 mAh cm–3, respectively
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 9
·1505
·
IF 2.467
Yan Song,Xu Zong,Nan Wang,Ning Yan,Xueying Shan,Jinchun Li
Lignin can be a candidate as a charring agent applied in halogen-free flame retardant polymers, and incorporation of silicon and nitrogen elements in lignin can benefit to enhancing its thermal stability and charring ability. In the present work, wheat straw alkali lignin (Lig) was modified to incorporate silicon and nitrogen elements by γ-divinyl-3-aminopropyltriethoxysilane, and the modified lignin (CLig) was combined with ammonium polyphosphate (APP) as intumescent flame retardant to be applied in poly(Lactic acid) (PLA). The flame retardancy, combustion behavior and thermal stability of PLA composites were studied by the limited oxygen index (LOI), vertical burning testing (UL-94), cone calorimetry testing (CCT) and thermogravimetric analysis (TGA), respectively. The results showed a significant synergistic effect between CLig and APP in flame retarded PLA (PLA/APP/CLig) occured, and the PLA/APP/CLig had better flame retardancy. CCT data analysis revealed that CLig and APP largely reduced the peak heat release rate (PHRR) and total heat release rate (THR) of PLA, indicating their effectiveness in decreasing the combustion of PLA. TGA results exhibited that APP and CLig improved the thermal stability of PLA at high temperature. The analysis of morphology and structure of residual char indicated that a continuous, compact and intumescent char layer on the material surface formed during firing, and had higher graphitization degree. Mechanical properties data showed that PLA/APP/CLig had higher tensile strength as well as elongation at break.Keywords:wheat straw soda lignin;silicon and nitrogen elements;poly(lactic acid);thermal stability;combustion behavior
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
·
2025
·
IF 3.1
Xinyan Yang,Xin Wang,Peng Zhu,Fei Han,Hongmei Ren,Zefeng Hua,Zhengbo Qin,Zhong-Fa Sun,Xianfeng Zheng
Reducing air interference is one of the most important steps in achieving direct determination of nitrogen element in water by laser-induced breakdown spectroscopy (LIBS). In this work, plasma amplification LIBS assisted with spatially resolved spectroscopy was used to reduce air interference in LIBS. The longitudinal spatially resolved spectrum of N I 746.831 nm at different breakdown position was obtained and optimized by imaging the plasma on the spectrometer entrance slit. By selecting the pixel range of plasma from 1-256 to 25-80, the background equivalent concentration (BEC) was reduced from 34.29 ppm to 9.58 ppm. Furthermore, the limit of detection (LoD), R2, the average relative error (REAV), and the root mean square error of cross validation (RMSECV) were improved from 2.01 to 0.53 ppm, 0.7779 to 0.9554, 24.76% to 15.22%, and 11.03 to 3.63 ppm, respectively. The results shown that the weak air interference and higher quantitative analysis performance of plasma amplification LIBS could be obtained by spatially resolved spectroscopy.
研究领域:
分析化学
·
光谱学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Weigao Han,Fang Dong,Weiliang Han,Jianfei Yao,Yu Meng,Zhicheng Tang
Selective exposure of dominant molecular space configurations and controllable synthesis of nanocomposites microstructure are full of challenge in improving the catalyst activity and designing materials. Herein, we precisely designed the size of ZIFs growing on nanofibers by changing the distribution of surface N elements. N elements microenvironment of nanofibers surface influenced not only ZIFs’ growth mechanism, but also its derivatives’ molecular space configurations (octahedral and tetrahedral structure of Co 3 O 4 ). To verify the influence of N element on space configurations, DFT were used to investigate structure preference energy (SPE). The result showed that the TEA (triethylamine)-induced method showed a big difference between octahedral and tetrahedral structure, indicating that this method was easier to generate octahedral complexes. Its derived Co 3 O 4 catalysts with more Co 3+ spieces showed the best catalytic performance (T 90 only 220 °C). Based on this, exposure of molecular space configurations will no longer be random but manipulable. The establishment of this new strategy will play an important role in the future catalyst design and realize the adjustable and controllable catalyst.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2022
·Vol. 29
·期 12
·1-11
·
IF 3.061
Yang Xiao,Duan Lian,Ran Xiaoqi,Ran Boli,Yi Shixiong
Conjugated microporous polymers (CMPs) have attracted great interest due to their high surface area, porosity and conjugacy, which could be potentially applied in pollutant adsorption, heterogeneous photocatalysis and super capacitor. Iodine 129 ( 129 I) and iodine 131 ( 131 I), as the common volatile radioactive products in nuke waste, have a long radioactive half-life, which is an important issue all the time. Here, two novel conjugated microporous polymers (TPAsTr-CMP and TPAPyD-CMP), which are rich in N element, were synthesized via Suzuki reaction and characterized through FTIR, 13 C NMR, SEM, TGA and etc. The surface areas calculated by BET are 449.1 m 2 /g for TPAsTr-CMP and 15.6 m 2 /g for TPAPyD-CMP, respectively. The iodine adsorption experiments at 350 K exhibited that the iodine uptake of TPAsTr-CMP was up to 3.52 g/g; while TPAPyD-CMP had the iodine uptake of 2.84 g/g. For dissolved iodine in cyclohexane, the TPAPyD-CMP performed a better adsorption capacity than TPAsTr-CMP. The adsorption capacity of TPAPyD-CMP was 333.8 mg/g, when initial iodine concentration was 500 mg/L, while that of TPAsTr-CMP was only 104.3 mg/g. The adsorption capacity to iodine should be attributed to their high surface area, effective adsorptive sites and expanded π-conjugated network.
研究领域:
材料科学
·
环境科学
·
放射化学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2021
·
IF 3.08
Weijie Ren,Jingjing Bai,Tingting Cai,Shijia Li,Ernan Pang,Hua Zhang,Zhenzhong Li
The heteroatom doping to achieve carbon dots has played a crucial part in exploring the fluorescence mechanism of multicolor emissions, which is closely related with the application development of such materials. Herein, a facile method was developed to synthesize three-color CDs via the co-doping of S and N elements with the assistance of ethanol solvent. The achieved CDs mainly emit blue, green and red lights, yet the photoluminescence quantum yields (FLQYs) generally decreases from 54.0% for B-CDs, 11.5% for G-CDs to 8.5% for R-CDs, respectively. Optical and structural characterizations of these CDs show that the variation of sp 2 - sp 3 hybridized domains resulted from the elements doping (S, N) fundamentally determines the color of CDs. The highest FLQYs of B-CDs in all CDs gives it an advantage to detect metal ions , which finds strong quenching only toward Ag + because of the interaction between Ag + and the cores. Likewise, these multicolor CDs attempt to fabricate CDs@PVP composite film emitted white-light as well as a clad material of WLED devices. The results indicate that the correlated color temperatures (CCT) in the ranges of cold and warm white lights can be obtained with different color rendering indexes (CRI) and luminous efficacies. Moreover, CCT and CRI are nearly up to the extremum at the same current value with increasing currents, implying that such CDs are potential as a kind of fluorescent nanomaterial to applicate to WLED device.
研究领域:
材料科学
·
纳米技术
·
光电技术
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）