MATERIALS LETTERS
·
2020
·
IF 3.204
Yun Zhang,Shihua Ding,Tianxiu Song,Yingchun Zhang
CoSnNb 2 O 8 ceramic with medium-permittivity was initially generated. Compositionally induced phase formation was identified by X-ray diffraction. Tetragonal rutile-type CoSnNb 2 O 8 was obtained from the reaction of SnO 2 with intermediate phase CoNb 2 O 6 . Both the dielectric constant ε r and quality factor Q × f initially increased with the sintering temperature, reaching the maxima at around 1225 °C, and declined thereafter. They were discussed based on the ionic polarizabilities and packing fraction, respectively. The temperature coefficient of resonant frequency τ f primarily depended on the Nb-site bond valence, as well as oxygen octahedra distortion. When sintered at 1225 °C, the CoSnNb 2 O 8 ceramic exhibited optimum properties with ε r = 31.8, Q × f = 43,000 GHz, and τ f = 35.01 ppm/°C.
研究领域:
材料科学
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无机非金属材料
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介电物理
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功能陶瓷
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微波材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 49
·期 5
·8204-8211
·
IF 5.532
Qianchao Ma,Qiyun Liu,Meihua Wu,Yifei Liu,Rui Wang,Ruxian Zhou,Yanheng Xu,Haichao Wei,Ruiyu Mi,Xin Min,Lefu Mei,Zhaohui Huang,Bin Ma
In this study, La 2 (MoO 4 ) 3 doped with Eu 3+ was synthesized by the high-temperature solid-state method. The phase composition of the Eu 3+ -doped La 2 (MoO 4 ) 3 sample was confirmed by X-ray powder diffraction (XRD) analysis, and the microstructure was observed via the scanning electron microscopy (SEM). Under the excitation at 211 nm, the room temperature emission spectra of Eu 3+ in the samples with different doping levels were recorded. In addition, the prepared La 2 (MoO 4 ) 3 : x Eu 3+ ( x = 0–0.25) phosphors were color tunable. A non-contact optical thermometer with high sensitivity and high-temperature resolution was fabricated based on the different thermal quenching behaviors of the Mo–O group and Eu 3+ center. The fluorescence intensity ratio (FIR), temperature resolution (ΔT), maximum absolute and relative sensor sensitivity (Sa and Sr) of La 2 (MoO 4 ) 3 :Eu 3+ were calculated according to different thermal quenching effects between room temperature (298K) and 573K of Eu 3+ and Mo–O group. These results show that La 2 (MoO 4 ) 3 :Eu 3+ has excellent sensitivity and temperature resolution, good reversibility and reliability, as Sa = 0.0525 K -1 , Sr = 0.3724. % K −1 , ΔT = 0.0806 K and the FIR error was only 0.62%. Therefore, the Eu 3+ -doped La 2 (MoO 4 ) 3 is a promising candidate material for high performance non-contact optical thermometers.
研究领域:
材料科学
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发光材料
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光学传感
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无机化学
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功能材料
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固体化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2024
·Vol. 59
·期 36
·16909-16917
·
IF 3.5
Xie Jingru,Fu Zhifen,Cheng Qing,Chen Chen,She Yubin,Li Xiangyi
Low temperature co-fired ceramics (LTCC) technology is extensively utilized to meet the requirements of device integration and miniaturization. Low-fired Li 3 Mg 2 NbO 6 ceramics doped with x wt% Li 2 O–MgO–B 2 O 3 –CaF 2 –SiO 2 glass (LMBCS, x = 0.5, 1.0, 1.5, 2.0) were prepared by the solid-state reaction method for applications in microwave communication materials. All samples exhibited a single-phase Li 3 Mg 2 NbO 6 structure. The addition of LMBCS glass effectively reduced the sintering temperature of Li 3 Mg 2 NbO 6 ceramics from 1250 °C to 875 °C. And adding LMBCS glass improved the Q × f value of Li 3 Mg 2 NbO 6 ceramics. The Li 3 Mg 2 NbO 6 -1.0wt% LMBCS ceramics exhibited outstanding microwave dielectric properties: ε r = 16.8, Q × f = 89,495 GHz, τ f = − 27.4 ppm/°C at 875 °C, which indicates that this ceramic is potential candidate materials for LTCC.
研究领域:
材料科学
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电子陶瓷
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功能材料
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无机非金属材料
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微波通信材料
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2020
·Vol. 221
·期 14
·2000144
·
IF 2.335
Guangfa Shi,Xiaomin Cai,Wenqiang Wang,Gengchao Wang
Polymeric positive temperature coefficient (PTC) materials can be used to install “brake” technology for the thermal runaway of lithium-ion batteries. However, it still has poor cycle stability and obvious negative temperature coefficient (NTC) effect, which reduces the reliability of the material. In order to solve these problems, conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) modified multilayer graphene (MLG) conductive additive (PEDOT-MLG) is introduced into middle density polyethylene/carbon black (MDPE/CB) system. Compared with the conventional modification, the PEDOT modified MLG shows high conductivity and excellent thermal stability. In addition, the introduction of PEDOT-MLG into MDPE/CB can further reduce the room temperature resistivity due to the good compatibility between the modified graphene and the matrix, thus improving the PTC intensity to 7.1. What is more, MLG limits the re-aggregation of CB particles when the temperature further rises, which effectively weakens the NTC effect.
研究领域:
高分子材料科学
·
功能材料
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能源材料
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纳米复合材料
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电学性能
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锂离子电池安全
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2019
·
IF 2.298
Xiaoda Wang,Yuan Gao,Chaoqun Li,Zhixian Huang,Ting Qiu
Liquid–liquid equilibrium data were determined for the two ternary systems of water + thioglycolic acid (TGA) + 2-ethyl-1-hexyl thioglycolate (ETE) and water + 2-ethyl-1-hexyl thioglycolate (ETE) + 2-ethyl-1-hexanol (EHL) at 293.15, 303.15, and 313.15 K under 101 kPa. The nonrandom two-liquid (NRTL) and universal quasi-chemical (UNIQUAC) activity coefficient models were used to correlate the experimental LLE data. The LLE data calculated by the NRTL and UNIQUAC models were in good agreement with the experimental ones.
研究领域:
化学工程
·
物理化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
·
2012
·
IF 3.35
Anning Wang,Hui Gao,Yanfang Sun,Yu-long Sun,Ying-Wei Yang,Guolin Wu,Yinong Wang,Yunge Fan,Jianbiao Ma
A series of temperature- and pH-responsive polyurethanes based on hexamethylene diisocyanate (HDI) and 4,4′-diphenylmethane diisocyanate (MDI) were synthesized by a coupling reaction with bis-1,4-(hydroxyethyl) piperazine (HEP), N -methyldiethanolamine (MDEA) and N -butyldiethanolamine (BDEA), respectively. The chemical structure , molecular weight, thermal property and crystallization properties were characterized by Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) spectroscopy. The resulting polyurethanes were then used to prepare nanoparticles either by direct dispersion method or dialysis method. Their pH and temperature responsibilities were evaluated by optical transmittance and size measurement in aqueous media. Interestingly, HDI-based and MDI-based polyurethanes exhibited different pH and temperature responsive properties. Nanoparticles based on HDI-HEP and HDI-MDEA were temperature-responsive, while MDI-based biomaterials were not. All of them showed pH-sensitive behavior. The possible responsive mechanism was investigated by 1 H NMR spectroscopy. The cytotoxicity of the polyurethanes was evaluated using methylthiazoletetrazolium (MTT) assay in vitro . It was shown that the HDI-based polyurethanes were non-toxic, and could be applied to doxorubicin (DOX) encapsulation. The experimental results indicated that DOX could be efficiently encapsulated into polyurethane nanoparticles and uptaken by Huh-7 cells. The loaded DOX molecules could be released from the drug-loaded polyurethane nanoparticles upon pH and temperature changes, responsively.
研究领域:
生物材料学
·
药剂学
·
肿瘤学
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高分子科学
·
纳米医学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2019
·Vol. 30
·期 10
·9983-9988
·
IF 2.195
Ma Panfei,Zhang Huimin,Chen Mingxing,Liu Ting,Chang Aimin,Su Zhi
Highly dense LaCrO 3 negative temperature coefficient (NTC) thermistor ceramics by low-heating solid-state method have been successfully synthesized in air ambient. The X-ray diffraction analysis has shown that both of the calcined powders and as-sintered ceramics crystallize in a perovskite structure. The relative densities of the ceramics synthesized by Cr(NO 3 ) 3 ·9H 2 O and the ceramics synthesized by CrCl 3 ·6H 2 O are 91% and 65%, respectively. The relationship between lnρ and 1000/T shows an approximate line in the measured temperature range. The values of ρ 25 and B 0/25 of the ceramics synthesized by Cr(NO 3 ) 3 ·9H 2 O and the ceramics synthesized by CrCl 3 ·6H 2 O are 424.8 Ω cm, 3252 K and 1835.9 Ω cm, 3636 K, respectively.
研究领域:
材料科学
·
无机非金属材料
·
电子陶瓷
·
热敏材料
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Zhongxuan Lin,Zhenluo Yuan,Huanhuan Zhang,Shuyan Guan,Xiaojiao Wang,Shiqian Zhao,Guangxin Fan,Yanping Fan,Baozhong Liu
Lowering the dehydrogenation temperature and maintaining high dehydrogenation capacity are greatly hindering the practical application of α-AlH 3 for the hydrogen fuel cell industry. Herein, the layered accordion-like V 2 C MXene is synthesized and doped into α-AlH 3 by mild ball milling . The 1 wt.% V 2 C-catalyzed α-AlH 3 possesses excellent dehydrogenation performance with a low initial decomposition temperature of 70.5 °C and a high hydrogen release capacity of 8.1 wt.%. Furthermore, 7.8 wt.% of hydrogen could be quickly released from α-AlH 3 -1 wt.% V 2 C composite within 15 min at 120 °C, with a lower activation energy of 69.5 kJ/mol than that of as-received sample. The excellent dehydrogenation performance is attributed to the high activity of the zero valence V catalyst which is transformed from the multivalent V during ball milling and to promote dissociation and reorganization of hydrogen. This effective approach significantly enhances the dehydrogenation of α-AlH 3 , providing a hopeful approach for modifying metal hydrides .
研究领域:
材料科学
·
无机化学
·
能源化学
·
纳米材料
·
储氢材料
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2014
·
IF 4.086
Hongjiao Nie,Yining Zhang,Wei Zhou,Jing Li,Baoshan Wu,Tao Liu,Huamin Zhang
The direct effect of nitrogen content and various nitrogen species on oxygen reduction reaction (ORR) activities in non-aqueous lithium-oxygen (Li-O 2 ) batteries are systematically investigated. Mesoporous carbon (MC) with various nitrogen species is prepared through heat treatment of N-containing precursor under different temperature. The effect of the heat treatment temperature on the performance of carbon materials in Li-O 2 battery is investigated. The bonding state of nitrogen atoms is found to have a significant effect on the ORR activity. The ORR activity in Li-O 2 battery is proved to be dependent on the quaternary N content while the total N content in the carbon material does not play a crucial role in the ORR process.
研究领域:
电化学
·
能源材料
·
纳米材料
·
电催化
·
锂离子电池
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2019
·
IF 2.29
Jing Fan,Bin Cui,Shuangshuo Liu,Fenhong Song,Xiaopo Wang
Biodiesel has been considered as one of the feasible attempts to replace the fossil fuels. Alcohols always played a role as the additives to improve the certain properties of biodiesel. In this work, the liquid thermal conductivity of binary mixtures of methyl laurate usually the significant biodiesel component with three alcohols (1-propanol, 1-butanol and 1-pentanol) was measured with the temperature ranging within 287 K to 358 K at atmospheric pressure. The total standard uncertainty of the experimental results was estimated to be less than 2% (in the 0.68 confidence level) and the repeatability was better than ±0.5%. In addition, three useful correlations for estimating the thermal conductivity of mixtures have been fitted and optimized, and the maximum deviation of three correlations were less than 1.30%.
研究领域:
能源化学
·
燃料科学
·
热物理性质
·
可再生能源
·
生物燃料
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2018
·
IF 3.23
Hui Liu,Sen Zhao,Zhengwen Xie,Kai Zhu,Xiaomeng Xu,Xuhan Ding,Adam Glowacz
The pyrophoric tendency of the powder of corrosion products and deposits in oil tanks was investigated by performing several series of tests in a modified self-heating experimental apparatus based on the crossing point temperature method. Three samples of the powder of corrosion products and deposits in oil tanks as well as a ferrous sulfide were used as test samples. The corresponding apparent activation energies ( E a s) were obtained: 26.1 kJ mol −1 for the corrosion products of a crude oil storage tank, 27.2 kJ mol −1 for the middle distillate oil storage tanks, and 43.5 kJ mol −1 for ferrous sulfide; the unexposed cross-point for deposits of a crude oil storage tank was at a temperature below 250 °C. Those values of E a s indicated that the corrosion products of the two oil storage tanks showed a stronger pyrophoric tendency than did the deposits of the crude oil storage tanks and ferrous sulfide. Furthermore, the E a values were similar to those of reactions reported for the incomplete oxidation of hydrogen sulfide (H 2 S), thus supporting the viewpoint that H 2 S may be considered the intermediate product for accelerating the self-heating and self-ignition of sulfide at temperatures below 250 °C and may play a major role in inducing fires and explosions in storage oil tanks. In addition, possible sources of H 2 S in self-heating of the corrosion product were largely caused by thermochemical sulfate reduction or thermal decomposition of the organic matter of oil tanks.
研究领域:
化学工程
·
安全工程
·
石油储运
·
燃烧学
·
材料腐蚀与防护
✓ 已验证
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2023
·
IF 6.4
Yuxin Shi,Jingwen Tang,Wanjie Sun,Haifeng Tang,Xinxin Xia,Tianyu Wang,Jianxiang Ding,Peigen Zhang,ZhengMing Sun
Metal whisker growth poses a significant reliability threat to electronic devices. Previous investigations have predominantly focused on metal platings and alloy solder samples, yet the intricate factors involved have yielded inconsistent comprehension of the phenomenon. To achieve a comprehensive understanding, exploring intermetallic compounds (IMCs) may offer a novel standpoint. Herein, we present the first report on the growth of single crystal cadmium (Cd) whiskers on Ti 2 Cd IMC, accompanied by the characterization of their composition, crystal structure, and morphological features. Furthermore, the influence of mechanical damage and temperature on the whisker growth is examined. Ball milling induces the decomposition of Ti 2 Cd, liberating active Cd atoms with elevated chemical potentials that consequently feed the whisker growth. These findings augment the existing knowledge on the topic of the metal whisker growth and provide fresh perspectives and references for further investigations in this field.
研究领域:
材料科学
·
金属腐蚀与防护
·
固态物理
·
电子器件可靠性
·
无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）