FASEB JOURNAL
·
2017
·Vol. 31
·期 4
·1756-1766
·
IF 5.498
Haijie Liu,Chunxiao Wan,Yanan Ding,Ranran Han,Yating He,Jinting Xiao,Junwei Hao
Experimental autoimmune neuritis (EAN) is a CD4 + T-cell–mediated autoimmune inflammatory demyelinating disease of the peripheral nervous system. It has been replicated in an animal model of human inflammatory demyelinating polyradiculoneuropathy, Guillain-Barré syndrome. In this study, we evaluated the therapeutic efficacy of a selective inhibitor of the immunoproteasome subunit, low-MW polypeptide 7 (PR-957) in rats with EAN. Our results showed that PR-957 significantly delayed onset day, reduced severity and shortened duration of EAN, and alleviated demyelination and inflammatory infiltration in sciatic nerves. In addition to significantly regulating expression of the cytokine profile, PR-957 treatment down-regulated the proportion of proinflammatory T-helper (T h )17 cells in sciatic nerves and spleens of rats with EAN. Data presented show the role of PR-957 in the signal transducer and activator of transcription 3 (STAT3) pathway. PR-957 not only decreased expression of IL-6 and IL-23 but also led to down-regulation of STAT3 phosphorylation in CD4 + T cells. Regulation of the STAT3 pathway led to a reduction in retinoid-related orphan nuclear receptor γ t and IL-17 production. Furthermore, reduction of STAT3 phosphorylation may have directly suppressed T h 17-cell differentiation. Therefore, our study demonstrates that PR-957 could potently alleviate inflammation in rats with EAN and that it may be a likely candidate for treating Guillain-Barré syndrome. —Liu, H., Wan, C., Ding, Y., Han, R., He, Y., Xiao, J., Hao, J. PR-957, a selective inhibitor of immunoproteasome subunit low-MW polypeptide 7, attenuates experimental autoimmune neuritis by suppressing T h 17-cell differentiation and regulating cytokine production. FASEB J . 31, 1756–1766 (2017) www.fasebj.org
研究领域:
免疫学
·
神经病学
·
药理学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Yongqing Wang,Fanbing Lai,Qikun Wang,Qinghua Long,Chao Wang,Wenjie Zhang,Qibing Chang
In this paper, high color performance Pr cation doped zircon (Pr-ZrSiO 4 ) yellow pigment has been prepared by inorganic sol-gel method. Meanwhile, the detailed process parameters for preparation of Pr-ZrSiO 4 pigment were systematically investigated. The research results indicate that the optimal process parameters are Pr-doping amount of 6 mol.%, calcination temperature of 900 °C, holding time of 2 h and Si/Zr ratio of 1.05. The synthesized Pr-ZrSiO 4 pigment shows an intense yellow hue, which chromatic parameters are L* = 81.84, a* = 4.36, b* = 70.55 and C* = 70.68. Moreover, the pigment shows outstanding tinting performance for ceramic glaze , suggesting its attractive application in ceramic decoration. XPS analysis demonstrated that the Pr cations in the Pr-ZrSiO 4 pigment consists of two valence states, namely trivalent and tetravalent. Finally, heterogeneously distributed behavior of Pr cations in the pigment was discovered.
研究领域:
材料科学
·
无机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Yalin Qin,Peikun Yan,Fuxuan Han,Yongcheng Zhang,Zonglin Lv,Chunming Zhou
The enhancement of both transparency and piezoelectric properties in transparent ferroelectric ceramics is a challenge. In this work, we prepared transparent 0.75Pb(Mg 1/3 Nb 2/3 )O 3 -0.25PbTiO 3 : x Pr 3+ ceramics by oxygen atmosphere sintering together with hot pressing sintering. When x = 1.5 mol%, a transparency of 68% @ 900 nm (close to the theoretical value ~71%) was achieved, and the piezoelectric properties increased to twice as much as those in undoped ceramics ( x = 0). The small average domain size (below 200 nm) that far below the visible light wavelength was believed to benefit light transmittance. Meanwhile, the minute amount of tetragonal component induced by Pr 3+ irons, was supposed to be responsible for the improved piezoelectric properties. These merits make Pr 3+ -doped 0.75PMN-0.25PT transparent ceramics promising functional materials for transparent piezoelectric devices.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2021
·
IF 6.024
Renjie Xie,Zhiwei Nie,Xiangchen Hu,Yi Yu,Carmela Aruta,Nan Yang
Developing inexpensive, efficient, and stable electrocatalysts for oxygen evolution reaction (OER) is crucial in energy conversion devices. The high cost and insufficient stability of the state-of-the-art IrO2 electrocatalysts for OER have restricted their widespread applications. In this work, La1–xPrxCoO3 perovskites with different Pr doping concentrations (x = 0, 0.25, 0.5, 0.75, 1) were investigated as alternative and inexpensive OER electrocatalysts. The OER activity was observed to increase with Pr doping and was maximum at the 50 mol % doping concentration. The overpotential of La0.5Pr0.5CoO3 was reduced to 312 mV at 10 mA·cm–2, which was significantly smaller than 371 mV of LCO and even superior to that of the commercial IrO2 catalysts (341 mV). Furthermore, La0.5Pr0.5CoO3 showed more stable performance in long-term tests compared with Pr0.5Ba0.5CoO3 and La0.6Sr0.4CoO3. X-ray diffraction analysis showed phase transition from a rhombohedral to an orthorhombic structure with Pr doping. Based on X-ray photoelectron spectrum analysis, the enhanced OER activity of La0.5Pr0.5CoO3 was correlated to electron occupation close to the Fermi level and the hybridization of O 2p and Co 3d bands, which facilitated the electron transfer process of the OER. Our work is therefore expected to provide a facile method of designing high-performance and stable OER perovskite catalysts through an approach based on electronic occupation regulation.
研究领域:
材料科学
·
电化学
·
能量转换
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 47
·20061-20070
·
IF 2.7
Jiabing Chen,Yibo Tang,Xiaojun Lu,Zijing Lu,Xingmao Jiang
The industrial production of methyl propionate synthesized via methoxycarbonyl esterification of ethylene achieved 100% atom economy. In this study, we synthesized ruthenium-loaded praseodymium–cerium oxide (Pr–CeO2) catalysts by precipitation impregnation and evaluated their performance in the methoxycarbonylation reaction of ethylene. The effect of Pr doping on the reaction results was analyzed by characterization and mechanistic studies. Pr doping increased the concentration of localized oxygen vacancies in the catalysts and thus modulated the catalytic effect of Lewis acid–base pairs. The increase of local oxygen vacancies significantly enhanced the activation and dissociation of CH3OH. At the same time, since the dissociation activation of the other two feedstock molecules, ethylene and CO, occurred at the Ru site, Pr doping facilitated the dispersion of Ru to a certain extent, thus increasing the dissociation activation of CO and ethylene, which, in combination with Pr doping, further increased the content of oxygen vacancies in the active site as methanol, resulting in a substantial enhancement of the dissociation activation of the feedstock molecules, which then increased the catalytic reaction rate through synergistic effects. The results provide a new perspective for the future study of methoxycarbonylation.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2026
·
IF 5.6
Yang Wu,Ying Dai,Yijun Liu,Libiao Xiao,Wen Chen,Xinmei Pei,Fanfeng Xie
In this study, a Pr–ZrSiO 4 pigment was synthesised using a solid-state method with Pr 6 O 11 , ZrO 2 and SiO 2 as raw materials and H 3 BO 4 as the mineraliser. Results demonstrated that as the temperature was increased from 1100 °C to 1400 °C, the H 3 BO 4 -containing Pr 0.08 Zr 0.92 SiO 4 sample underwent a distinct colour transition from yellow (1100 °C–1200 °C) to green (1250 °C–1400 °C). By contrast, the sample without H 3 BO 4 maintained a yellow hue between 1100 °C and 1400 °C. Transmission electron microscopy analysis revealed Pr 2 Zr 2 O 7 secondary phase dispersed in ZrSiO 4 of the green powders. The added H 3 BO 4 reacted with SiO 2 to form a borosilicate glass phase that exhibited a strong adsorption capacity for lattice oxygen, resulting in the generation of oxygen vacancies in ZrSiO 4 . To maintain valence balance, Pr 4+ (yellow) converted to Pr 3+ (green) and the secondary phase Pr 2 Zr 2 O 7 was formed in ZrSiO 4 . The valence state transition of Pr ions (Pr 4+ /Pr 3+ ) was the primary reason for the colour transition. The green pigment exhibited excellent high-temperature stability, showing potential application in the ceramic industry.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 1
·147-153
·
IF 3.9
Hongzheng Li,Ying Li,Bo Li,Wenlong Huang,Yushi Ding
ReNiO3 (Re = Pr, Sm, Eu) solid electrolytes were prepared by the sol–gel method, which were sintered in a pure oxygen atmosphere of 20 MPa at 1000 °C for 24 hours. The DC resistivities of the three materials in air and in a hydrogen-containing atmosphere were tested respectively. The resistivities in the hydrogen-containing atmosphere were about 102, 104, and 105 times higher than those in air and XPS analysis showed that after 10%H2–Ar treatment, the proportion of Ni2+ of PrNiO3, SmNiO3 and EuNiO3 increased successively. The proton transport number of PrNiO3 was lower than 0.5 at 50–500 °C, and SmNiO3 and EuNiO3 were almost pure proton conductors below 200 °C. The conductivities of SmNiO3 and EuNiO3 were 1.08 × 10−4 S cm−1 and 1.83 × 10−5 S cm−1 at 200 °C in 5%H2–Ar. The hydrogen sensing properties of SmNiO3 and EuNiO3 show that the measurement results of the two materials were accurate in the range of 0.5–10% H2.
研究领域:
材料科学
·
固态离子学
·
能源材料
·
无机化学
·
传感器技术
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Chenglong Xia,Jiahui Yang,Bingyang Zeng,Chunmiao Cui,Haoyuan Weng,Yue Guo,Xiaoguang Liu,Ling Li
This study successfully synthesized Na 5 Y(WO 4 ) 4 doped with Sm³⁺, Pr³⁺, and Tb³⁺ using a high-temperature solid-state method. Photoluminescence spectra revealed that Na 5 Y(WO 4 ) 4 :Sm³⁺ phosphors emits a strong red glow at 646 nm under the excitation of 405 nm, and has an extremely high quantum yield, suggesting their suitability for plant growth LED lighting applications. In contrast, Na 5 Y(WO 4 ) 4 :Pr³⁺ phosphors displayed a lower efficiency but still aligned well with the red-wavelength absorption spectra of plants. Additionally, Na 5 Y(WO 4 ) 4 :Tb³⁺ phosphors demonstrated strong green emission under UV light, indicating potential applications in fingerprint detection. The Site Occupancy Theory (SOT) was utilized to explain the preferential occupation of dopant ions, showing that Sm³⁺ and Tb³⁺ preferred Y1 sites, whereas Pr³⁺ favored Na2 sites.
研究领域:
材料科学
·
光学
·
农业科学
·
法医学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2018
·
IF 3.794
Ting Chen,Jianrui Zha,Xiaojun Zhang,Xiaobo Hu,Weihui Jiang,Zhixiang Xie,Wan Jiang
Yellow inorganic pigments Pr x Zr 1-x SiO 4 (x = 0–0.08) have been prepared by a novel non-hydrolytic sol-gel (NHSG) method at 750 °C for 2 h. Replacing Pr 4+ for Zr 4+ in ZrSiO 4 increased the cell volume and changed the color from white to yellow gradually. The Si―O―Zr and Si―O―Pr bands were observed in the FT-IR spectra of xerogel , indicating it could reach homogeneous mixing at the atomic level. Therefore, it promoted the solid solution reaction between Pr and zircon at low temperature. The samples exhibit high doping limitation (x = 0.08) and brilliant yellow hue ( b * = 69.48) in contrast with the previously reported praseodymium zircon yellow pigments. The intense of yellow hue was increased with increasing the Pr doping content due to the increase of Pr 4+ /Pr 3+ species. After applying on bisque ceramic tiles, the pigment exhibited excellent coloration, high thermal stability and low solubility in molten glazes, indicating its potential application in ceramic decoration.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2022
·
IF 3.898
Ye Zhang,Yong Gao,Peng Wang,Duo Na,Zhenming Yang,Jinsong Zhang
Recently, there has been considerable interest in the use of microchannel reactors for hydrometallurgy of rare earths (REs). Here, a novel integrated microchannel reactor based on the hollow-strut SiC foam material is presented and demonstrated to extract Ce 3+ and Pr 3+ using 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (P507) as the extractant. The typical three-dimensional reticulated structure of the hollow-strut SiC foam was characterized by scanning electron microscopy and X-ray micro computed tomography. Since the reactor’s structure plays a key role in fluid mixing and mass diffusion during the extraction process, the structure-performance relationship of the foam was studied by extraction experiments combined with numerical simulations. Using the foam with the optimal structure, the influence of the flow rate Q 0 of the two liquid phases on the extraction efficiency η and overall volume mass transfer coefficient K L a was discussed. For both RE ions, with increasing Q 0 , η decreases while K L a increases. For the total flow rate of the two phases of 4 ml⋅min −1 , the η values of Pr 3+ and Ce 3+ reached 98.7% and 97.0%, respectively. For the total flow rate of 36 ml⋅min −1 which was much higher than that of many other microchannel reactors reported in the literatures, the η values of Pr 3+ and Ce 3+ still reached 92.2% and 86.9%, respectively, and the K L a values of Pr 3+ and Ce 3+ were 0.198 and 0.161 s −1 , respectively, similar to the high values reported for other microchannel reactors studied in previous work. These findings indicate that the hollow-strut SiC foam microchannel reactor is suitable for use in REs extraction.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Electronic Materials
·
2021
·
IF 3.314
Xianghua Wang,Zhiliang Xu,Shaoqi Zhuo,Peng Hu,Yong Yang,Bin Zhou,Wen-Hua Zhang
High performance CsPbBr3 nanocrystals (NCs) were synthesized via a hot injection method followed by a room-temperature ligand exchange modification using 3-mercaptopropyltrimethoxysilane (MPTMS). The ligand exchange promotes crystal growth and enhances the photoluminescence quantum yield (PLQY) of the NCs to near unity. The oscillator strength of the interband transition based on UV–vis absorption was surprisingly amplified by a factor of 2.5. The NC’s surface was passivated via S–Pb polar covalent bonding, which shifts the thermodynamic equilibrium and favors NC growth with a higher Br-to-Pb atomic ratio on the surface. Moreover, the perovskite lattice was strained by a cross-linked polymeric network of self-condensed siloxane. The strain within CsPbBr3 NCs was modulated by mixing at room temperature with Cs3PrCl6 NCs for controlled halide exchange and Pr doping; thereby blue emission from the Pr-doped CsPb(Cl/Br)3 NCs was achieved with optimized brightness (PLQY = 88%) at 464 nm.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2026
·
IF 8.3
Haoyun Zhao,Jiahui Xu,Hongsen Xie,Shasha Li,Xiaoning Wang,Feifei Wang,Davoud Dastan,Xingtai Chen,Xi-Tao Yin,Xiaoming Tan,Xiaoguang Ma
This study employed a one-step hydrothermal method to prepare pure MoS₂ samples and Pr-doped MoS₂ materials. MoO₃ and Pr-doped MoO₃-based Triethylamine gas sensors were fabricated through calcination. The elemental composition and morphology of the materials were investigated using characterization techniques including XPS, XRD, and SEM. Effective substitution of Pr³ ⁺ ions for Mo⁶⁺ lattice sites was achieved, yielding layered stacked rectangular prism nanomaterials composed of rectangular sheets of varying dimensions. At its optimal operating temperature of 250 °C, the sensor exhibited high response, rapid recovery, excellent selectivity, repeatability, long-term stability, and moisture resistance. The significantly enhanced response to Triethylamine is attributed to Pr doping, which promotes surface oxygen adsorption and increases oxygen vacancy concentration. This modification intensifies electron capture, widens the electron depletion layer, and facilitates a greater release of trapped electrons upon gas exposure. Consequently, the surface potential barrier is sharply reduced, leading to a pronounced macroscopic resistance transition. A detailed mechanistic analysis of this sensing behavior is provided.
✓ 已验证
DOI
高影响因子
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