JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2023
·Vol. 107
·期 1
·223-233
·
IF 3.9
Zhenjun Qing,Huapeng Zou,Xin Zhou,Haiyan Li,An Liu,Shumin Duan,Yingxiang Li,Sen Peng
Li 2 Co 2 Mo 3 O 12 (LCMO) ceramics were synthesized using the solid-state reaction method. X-ray diffraction analysis results indicated that the sole crystalline phase present in the ceramics was LCMO, which belongs to the orthorhombic structure of the Pnma space group. The sample, which was sintered at 850°C, demonstrated outstanding microwave dielectric properties, with an ε r value of 8.95, a Q × f value of 43 200 GHz, and a τ f value of –71.3 ppm/°C. It was found that while the main factor influencing ε r was ionic polarizability, sintering density had a lesser effect on it. Furthermore, Q × f was primarily affected by relative density, and there was no significant relationship between packing fraction and this property. The higher the degree of distortion of the [Li/CoO 6 ] octahedron is, the poorer the τ f value of LCMO ceramics. Additionally, the microwave dielectric properties of LCMO ceramics were intrinsically linked to ionicity, lattice energy, bond energy, and thermal expansion coefficient of chemical bonds, with Mo–O bonds being the primary factor affecting these properties, as supported by analysis using chemical bonding theories. Mo–O bond vibration dominated the Raman spectra. Good chemical compatibility between silver and LCMO ceramics was demonstrated through our co-firing experiment.
研究领域:
材料科学
·
陶瓷
·
微波介质
·
固态化学
·
拉曼光谱
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
·
2021
·
IF 5.875
Degong Yang,Chao Liu,Dawei Ding,Peng Quan,Liang Fang
Though ionic liquids (ILs) as novel enhancers had garnered wide attention, detailed studies elucidating molecular design of drug-ILs were missing and mechanisms of their formation and skin permeation were still lacking. Herein, we systematically investigated effects of counterions structures on formation and skin permeation of drug-ILs. Firstly, effects of counterions on formation of drug-ILs were dependent on polarizability, molecular weight (M.W.) and polar surface area of counterions. It was caused by strong charge assisted hydrogen bond and van der Waals interactions revealed through FT-IR, X-ray photoelectron spectroscopy and molecular docking, which undermined ionic interactions and reduced total interaction strength, thereby produced lower lattice energy. Then, skin permeability of drug-ILs had a good parabola relationship with M.W., polarizability and log P of counterions. The underlying mechanism was the increased drug miscibility with stratum corneum, which caused conformational disorder and phase transition of lipid bilayers characterized by ATR-FTIR, DSC and confocal laser scanning microscopy. Finally, the drug-ILs proved to be non-irritating using in vivo skin erythema analysis. In conclusion, the quantitative structure-activity relationship models based on counterions structure to predict formation and skin permeation of drug-ILs were developed, which provided basic theory for design of drug-ILs with high permeation-enhancing efficiency.
研究领域:
药剂学
·
药物化学
·
材料科学
·
生物物理学
✓ 已验证
DOI
高影响因子
Nature Photonics
·
2024
·
IF 32.3
Zhou Yang,Guo Zhengfeng,Gu Honggang,Li Yanqiang,Song Yipeng,Liu Shiyuan,Hong Maochun,Zhao Sangen,Luo Junhua
Optical anisotropy, a spatially asymmetric light–matter interaction that manifests itself as birefringence and dichroism, is paramount for manipulating light polarization in modern optics. So far, various natural birefringent crystals are widely used, but their birefringence is limited to <0.3. Here we demonstrate a solution-processable natural crystal C 3 H 8 N 6 I 6 ·3H 2 O with giant birefringence up to 2.8 within the visible to infrared spectral region. Combining critical point analysis and the first-principles calculations, we reveal that this giant optical anisotropy mainly comes from the linear (I 3 ) − structural units in a parallel arrangement, which maximizes the difference of polarizability along the different crystallographic axes. This work highlights the potential of natural polyiodide crystals as an outstanding platform to satisfy the increasing demand for photonic applications that exploit polarization in optical communication, three-dimensional imaging, ultrahigh-resolution sensing and other tasks.
研究领域:
材料科学
·
光学
·
光子学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Deqin Chen,Xiaowei Zhu,Siyu Xiong,Guobin Zhu,Laijun Liu,Jibran Khaliq,Chunchun Li
In this study, (La0.2Nd0.2Sm0.2Ho0.2Y0.2)(Nb1–xVx)O4 (0.1 ≤ x ≤ 0.4) ceramics were prepared using a high-entropy strategy via the solid-phase method. The crystal structure, microstructure, vibration modes, and phase transition were studied by X-ray diffraction, scanning electron microscopy/transmission electron microscopy (SEM/TEM), and Raman spectroscopy techniques. The phase of ceramics was confirmed to be a monoclinic fergusonite in the range of x ≤ 0.28, a tetragonal scheelite was in the range of 0.3 ≤ x ≤ 0.32, a complex phase of tetragonal scheelite, and zircon was observed in the ceramics when x ≥ 0.35. A zircon phase was also detected by TEM at x = 0.4. The ceramic at x = 0.25 exhibited outstanding temperature stabilization with εr = 18.06, Q × f = 56,300 GHz, and τf = −1.52 ppm/°C, while the x = 0.2 ceramic exhibited a low dielectric loss with εr = 18.14, Q × f = 65,200 GHz, and τf = −7.96 ppm/°C. Moreover, the permittivity, quality factor, and the temperature coefficient of resonance frequency were related to the polarizability, packing fraction, density, and the temperature coefficient of permittivity caused by phase transition. This is an effective method to regulate near-zero τf by the synergism of the high-entropy strategy and substituting Nb with V in LnNbO4 ceramics.
研究领域:
材料科学
·
电气工程
·
物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2019
·
IF 6.361
Qi Peng,Xuehua Weng,Wenqiang Xie,Meihui Ying,Xucong Lin,Yongwei Dai,Qunying Yu,Haibo Pan,Junshao Liu,Min Du
Quick recombination of photogenerated electrons and holes in photocatalytic process remains a huge challenge. And the routine efforts are concentrated on heterojunction , metal decoration and surface defect strategies. PbTiO 3 as a typical perovskite ferroelectrics is with a strong built-in electric field as self-junction caused by internal spontaneous polarization, facilitating the charge separation in the photocatalytic process. Here, under UV irradiation , L-shaped PbTiO 3 with active (1 1 0) facet as a photocatalyst was applied to photo-reduce graphene oxide (GO), where a specific reduced graphene oxide (rGO)/PbTiO 3 composite was synthesized in presence of isopropanol, a hole-trapping agent. According to the linear optical properties , the polarizability of PbTiO 3 is calculated to 1.01 × 10 −23 cm 3 (2.68 times that of P25 (TiO 2 )), inducing the photo-excited charge separation by PbTiO 3 . Based on XPS characterization, a Ti O C chemical bond is identified on the interface between rGO and PbTiO 3 . The response peak current for an electrochemical sensor based on rGO/PbTiO 3 was proportional to the concentration of pyrrole (6.6 × 10 −9 –3.1 × 10 −7 M, R 2 = 0.999), and an extremely low limit reaches to 2.38 × 10 −9 M. In addition, polypyrrole during the pyrrole detection was realized by the multi-cycle oxidation process . And also, the electrochemical detection has been successfully applied for the pyrrole quantification in real samples.
研究领域:
材料科学
·
电化学
·
纳米技术
·
催化
·
分析化学
✓ 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）