JOURNAL OF LUMINESCENCE
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2019
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IF 2.961
Su Zhang,Lingling Lv,Hongjie Wang,Chongyang Zhu,Ran Pang,Jing Feng,Da Li,Guanyu Liu,Lihong Jiang,Chengyu Li
The 0.8CaWO 4 -0.2EuMO 4 (M = Nb, Ta) solid solution and Eu 3+ , Ta 5+ and Nb 5+ single doped CaWO 4 were prepared by a high-temperature solid state reaction technique. Experiments show that the addition of Nb 5+ and Ta 5+ can increase the red luminescence of Eu 3+ in CaWO 4 . In this paper, the composition and structure of solid solution were analyzed by X ray diffraction (XRD), Fourier transform infrared spectrum and Raman spectrum analysis. The luminescence properties of the solid solution were studied by means of stable photoluminescent spectra, diffuse reflectance spectra (DRS), fluorescent decay curves and variable temperature spectra. By combining structural analysis, J-O theoretical calculation and experimental results, we believe that the significant improvement of the emission efficiency comes from the decrease of non-radiation relaxation rate.
研究领域:
材料科学
·
光学
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产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
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2020
·
IF 5.289
Chenyao Li,Shaolong Li,Yusi Che,Junyi Li,Yongchun Shu,Jilin He,Jianxun Song
The reduction mechanism of Nb(V) in molten KCl-NaCl at 1023 K was investigated by a series of electrochemical techniques such as cyclic voltammetry, square wave voltammetry and chronopotentiometry. It was found that there were three steps in the reduction of Nb(V) as Nb(V)→Nb(III)→Nb(I)→Nb, and electrochemical reaction, Nb(V)→Nb(III), is a quasi-reversible diffusion controlled process. The diffusion coefficient of Nb(V) was also obtained by cyclic voltammetry, square wave voltammetry and chronoamperometry. The relationship between current density and the square root of time shows that the nucleation of niobium belongs to the instantaneous nucleation on molybdenum electrode in molten KCl-NaCl-NbCl 5 (0.43 × 10 −3 mol/cm 3 ) at 1023 K at −3.10 V vs. Cl 2 /Cl − . Moreover, the metallic niobium was deposited on molybdenum wire by chronoamperometry, and the products were analyzed by scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX). The results showed that the metallic niobium has a high purity of 99.98%.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
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2015
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IF 4.513
Xueni Sun,Xiaodan Liu,Jianan Feng,Yan Li,Chunhui Deng,Gengli Duan
Rapid and selective enrichment of phosphopeptides from complex biological samples is essential and challenging in phosphorylated proteomics. In this work, for the first time, niobium ions were directly immobilized on the surface of polydopamine-coated magnetic microspheres through a facile and effective synthetic route. The Fe 3 O 4 @polydopamine-Nb 5+ (denoted as Fe 3 O 4 @PD-Nb 5+ ) microspheres possess merits of high hydrophilicity and good biological compatibility, and demonstrated low limit of detection (2 fmol). The selectivity was also basically satisfactory (β-casein:BSA = 1:500) to capture phosphopeptides. They were also successfully applied for enrichment of phosphopeptides from real biological samples such as human serum and nonfat milk. Compared with Fe 3 O 4 @PD-Ti 4+ microspheres, the Fe 3 O 4 @PD-Nb 5+ microspheres exhibit superior selectivity to multi-phosphorylated peptides, and thus may be complementary to the conventional IMAC materials.
研究领域:
生物化学
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分析化学
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蛋白质组学
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DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2022
·Vol. 105
·期 12
·7455-7466
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IF 4.186
Fangyi Huang,Hua Su,Qin Zhang,Xiaohui Wu,Yulan Jing,Yuanxun Li,Xiaoli Tang
The BaZnP 2− x Nb x O 7 microwave dielectric ceramics were prepared by solid-state reaction method to investigate the impact of Nb 5+ on the composition, microstructure, and vibrational properties, as well as sintering characteristics and microwave dielectric properties. The solubility of Nb 5+ in the BaZnP 2− x Nb x O 7 lattice was limited. A moderate amount of Nb 5+ substitution could promote the densification process. The vibrational characteristics of the BaZnP 2 O 7 ceramics were first studied by performing experimental and theoretical Raman and infrared spectroscopy measurements in this work, and their relationship with the microwave dielectric properties was studied. The acquired results showed that (Ⅰ) ε r was influenced by both the density and the second phase; (Ⅱ) the density and full width at half maximum of the Raman vibrational peak played a critical role in affecting the Q × f values. The BaZnP 2− x Nb x O 7 samples sintered at 925°C exhibited the outstanding microwave dielectric properties with x = 0.02: ε r = 7.98, Q × f = 60 615 GHz (tan δ = 2.18 × 10 −4 ; f = 13.21 GHz) and τ f = −52.93 ppm/°C ( ρ bulk = 4.03 g/cm 3 ; ρ r = 92.69%). The proposed ceramic is expected to be used in microwave substrates.
研究领域:
材料科学
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物理学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2019
·Vol. 30
·期 15
·14528-14537
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IF 2.195
Zeng Yuan,Li Zhicheng,Shao Junming,Wang Xianchi,Hao Wenbin,Zhang Hong
Cu/Nb doped YFeO 3 ceramics were synthesized through wet chemical method followed by traditional ceramic sintering technology. The phase component and electrical properties of the ceramics were investigated. The XRD pattern shows that all the prepared ceramics have the orthorhombic perovskite structure with space group of P nma . The XPS analysis demonstrates the existence of Fe 2+ and Fe 3+ in the ceramics. The temperature dependence of resistivity indicates that YFeO 3 -based materials have a characteristics of negative temperature coefficient (NTC) of resistivity. The room temperature resistivities (306–1.52 × 10 5 Ω cm) and temperature sensitivity B values (2693–5395 K) can be effectively adjusted by changing the contents of Cu- and Nb- ions. According to the analysis of complex impedance spectra at various temperatures, the NTC characteristic could be attributed to grain effect and grain boundary effect. The possible conduction mechanisms are propose to hopping conduction and band conduction in grain, and thermal activation transport of charge carries in grain boundary.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2022
·Vol. 414
·期 27
·7885-7895
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IF 4.478
Zhang Xiaoya,Feng Quanshou,Xie Zehu,Xu Fuxing,Yan Yinghua,Ding Chuanfan
In this work, on the basis of an immobilized metal ion affinity chromatography enrichment strategy, a new kind of covalent organic framework (COF) material for enrichment of phosphorylated peptides and exosomes was successfully prepared in a facile method, and Ti 4+ and Nb 5+ were used as dual-functional ions (denoted as COF-S–S-COOH-Ti 4+ /Nb 5+ ). With the advantage of unbiased enrichment towards phosphopeptides, COF-S–S-COOH-Ti 4+ /Nb 5+ shows ultra-high selectivity (maximum molar ratio of β -casein: BSA is 1:20,000) and low limit of detection (0.2 fmol). In addition, the material has an excellent phosphopeptide loading capacity (100 μg/mg) and reusability (at least seven times). Furthermore, applying the material to the actual sample, 4 phosphopeptides were selectively extracted from the serum of renal carcinoma patients. At the same time, exosomes with an intact structure in the serum of renal carcinoma patients were successfully isolated rapidly using this strategy. All experiments have shown that COF-S–S-COOH-Ti 4+ /Nb 5+ exhibits exciting potential in practical applications. Graphical abstract
研究领域:
分析化学
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生物医学工程
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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）