Journal of Materials Chemistry C
·
2024
·Vol. 12
·期 28
·10513-10531
·
IF 5.7
Xiaoqiang Xiong,Xiaodong Jing,Zitao Chen,Qianqian Zhao,Zuoguang Li,Xi Yang,Qun Wang,Tongyun Zhao,Huayang Gong
Using single loss type media as microwave absorbers to simultaneously achieve low reflection loss, wide-band absorption and thin thickness is a huge challenge. In this work, to combine the high dielectric loss of Pr-doped M-type strontium ferrite and the high magnetic loss of W-type hexaferrites, we improved the traditional sol–gel auto-combustion method via increasing an extra sintering process and successfully prepared xSrPr0.5Fe11.5O19/yBaCo2Pr0.5Fe15.5O27 (x : y = 2 : 1, 1.5 : 1, 1 : 1, 1 : 1.5 and 1 : 2) M/W (M-type hexaferrite/W-type hexaferrite) composite materials with a unique “inlay structure”. The M-phase and PrFeO3-type phase were partially wrapped by the huge W-phase, which resulted in enhanced exchange coupling. Benefitting from the exchange coupling and huge grains, the coercivity and anisotropy fields of composite hexaferrites decreased. Therefore, the natural resonance frequencies of some samples reduced to within 18.00 GHz. High magnetic loss occurs while dielectric loss is preserved due to strong resonance interaction and multiple polarization relaxation mechanisms. Hence, the composite hexaferrites exhibit satisfactory microwave absorption performance on account of the magnetic–dielectric synergistic effect. The effective absorption bandwidth of the prepared materials can cover X and Ku bands at thin matching thicknesses (<2.00 mm). The minimum reflection loss reaches −56.30 dB (d = 1.97 mm), and the maximum effective absorption bandwidth reaches 8.17 GHz (d = 1.63 mm). This work will provide new ideas for improving the absorption performance of ferrite composite materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Xin Zhou,Nianjun Hou,Tian Gan,Lijun Fan,Yongxin Zhang,Jingyu Li,Ge Gao,Yicheng Zhao,Yongdan Li
BaCe 0.2 Fe 0.8-x Pr x O 3-δ (x = 0–0.3) is studied as a cobalt-free cathode material for proton-conducting solid oxide fuel cells. The cathode is composed of a cubic BaFeO 3-δ phase and an orthorhombic BaCeO 3-δ phase, and Pr is doped in both phases. The partial substitution of Pr for Fe decreases the content of the BaFeO 3-δ phase, leading to a lower electrical conductivity . BaCe 0.2 Fe 0.6 Pr 0.2 O 3-δ has the most adsorbed oxygen and Fe 3+ on the surface, resulting in the fastest oxygen surface exchange kinetics and the highest activity. The partial pressure of H 2 O shows a negligible effect on the polarization resistance of the cathode. In contrast, the polarization resistance increases remarkably with the decrease of oxygen partial pressure , indicating that the rate of the cathode process is controlled by the surface exchange of oxygen. At 700 °C, BaCe 0.2 Fe 0.6 Pr 0.2 O 3-δ shows the lowest polarization resistance of 0.057 Ω cm 2 , and a single cell with that cathode exhibits the highest maximum power density of 562 mW cm −2 . The results demonstrate that Pr doped BaCe 0.2 Fe 0.8 O 3-δ is a promising cobalt-free cathode material for proton-conducting solid oxide fuel cells.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Jiabing Chen,Xiaowei Zhu,Mengheng Wang,Xingmao Jiang,Xiaojun Lu
The reaction rate of alkoxycarbonylation is typically lower when using heterogeneous catalysts compared to homogeneous catalysis, primarily due to the reduced ability of the active sites to activate the reactants. To address the insufficient activation of reactants on the Ru/CeO 2 catalyst for ethylene methoxycarbonylation, this study investigates the doping of CeO 2 with Pr 3+ ions. By substituting Ce 4+ with Pr 3+ in the CeO 2 , richer oxygen vacancies are generated, which enhance the activation of CH 3 OH. This doping significantly increases the reaction rate of ethylene methoxycarbonylation to methyl propionate (MP), achieving a rate of 86.1 g·g Ru -1 ·h −1 while maintaining a selectivity of over 99 %. Notably, Pr doping also induces the formation of Ru-O-Ce species in the catalyst, which hinders the reduction of Ru species. However, this hindered reduction is counterbalanced by the enhanced dispersion of Ru species, as Pr doping promotes the formation of smaller Ru nanoparticles. Thus, an optimal level of Pr doping exerts a synergistic effect by positively influencing both the CeO 2 support and the Ru metal, thereby improving their respective abilities to activate the reactants and enhancing the overall performance in the ethylene methoxycarbonylation reaction to produce MP.
研究领域:
催化
·
材料科学
·
化学反应工程
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Gulizhabaier Abulipizi,Zimin Yu,Shaochen Lin,Nan Zhang,Fang Xu,Xin Wang,Zhanjun Li
Chromium-doped persistent luminescence nanoparticles (PLNPs) have promising biomedical applications in X-ray charged near-infrared (NIR) luminous imaging. The persistent luminescence (PersL) property was usually adjusted by co-doping with other ions. Impurity phases were thought to be adverse to the PersL. In this study, a composite material, LiInSi 2 O 6 :Cr,Pr·2SiO 2 (LICP-S), was synthesized with a PersL peak at 800 nm after being charged by 1 Gy X-ray while LiInSi 2 O 6 :Cr (LIC) and LiInSi 2 O 6 :Cr,Pr (LICP) possessed no or very weak PersL. Distinctively, excess metastable cristobalite silica was found essential for the much more intense PersL of LICP-S than LICP and LIC. Thermostimulated luminescence spectra studies indicated that cristobalite adjusted the Pr-related traps from deep traps to shallow ones, which facilitated the room temperature PersL. The low dose X-ray charged PersL of LICP-S was applied to demonstrate the luminous labeling of a medical silicone prosthesis that was supposed to be imbedded in body for years via X-ray activated PersL imaging in vitro and in vivo . This work not only provides a kind of PLNPs with 800 nm emission suitable for low dose X-ray activation, but also an unusual strategy for trap engineering in PersL materials by designing multi-phase composites.
研究领域:
材料科学
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生物医学工程
·
医学影像学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Advanced Ceramics
·
2022
·Vol. 11
·期 11
·1801-1814
·
IF 11.534
Cheng Fuhao,Zhang Fengnian,Liu Yufeng,Guo Meng,Cheng Chufei,Hou Jiadong,Miao Yang,Gao Feng,Wang Xiaomin
Environmental barrier coatings (EBCs) with excellent chemical resistance and good high-temperature stability are of great significance for their applications in next-generation turbine engines. In this work, a new type of high-entropy fluorite-structured oxide (Ce 0.2 Hf 0.2 Y 0.2 Pr 0.2 Gd 0.2 )O 2− δ (HEFO-1) with different Ti 4+ contents were successfully synthesized. Minor addition of Ti 4+ could be dissolved into a high-entropy lattice to maintain the structure stable, effectively reducing the phase formation temperature and promoting the shrinkage of bulk samples. Heat treatment experiments showed that all the samples remained a single phase after annealing at 1200–1600 °C for 6 h. In addition, high-entropy (Ce 0.2 Hf 0.2 Y 0.2 Pr 0.2 Gd 0.2 Ti 0.2 x )O 2− δ demonstrated great resistance to calcium—magnesium—alumina—silicate (CMAS) thermochemical corrosion. When the content of Ti was increased to x = 0.5, the average thickness of the reaction layer was about 10.5 after being corroded at 1300 °C for 10 h. This study reveals that high-entropy (Ce 0.2 Hf 0.2 Y 0.2 Pr 0.2 Gd 0.2 Ti 0.2 x )O 2− δ is expected to be a candidate for the next-generation EBC materials with graceful resistance to CMAS corrosion.
研究领域:
材料科学
·
涂层
·
高温材料
·
腐蚀抗性
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Jian Fang,Jing-Jing Xue,Rong-Pu Xiao,Xi Chen,You-Min Guo,Ji-Ming Song
The development of high performance triethylamine (TEA) sensors for the protection of human safety is essential. Herein, we reported a promising semiconductor metal oxide (SMO) gas sensor based on Pr-doped ZnO nanospindles as the sensing materials for the detection of TEA. The elemental composition and micromorphology of the as-prepared samples were systematically analyzed. The gas sensing performance of the pristine, 1 mmol%, 2 mmol%, and 3 mmol% Pr-ZnO sensor was evaluated. Among them, the 2 mmol% Pr-ZnO sensor exhibited the highest response value for TEA gas, and reached 158.0 towards 50 ppm TEA at 200 °C, which was about 10.0-fold higher than the response value of the pristine ZnO sensor. In addition, the 2 mmol% Pr-ZnO sensor also showed good reproducibility, rapid response/recovery time (10/46 s), theoretical limit of detection (168 ppb), outstanding long-term stability, and excellent selectivity for TEA gas.
研究领域:
材料科学
·
化学传感器
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
BIOMATERIALS
·
2025
·
IF 12.9
Ge Yang,Xiongke Hu,Xiaochuan Li,Liudang Fang,Zhipei Tong,Zhenyuan Yin,Yu Cai,Lingrong Zeng,Gencheng Gong,Yufeng Zheng,Dong Bian
Contrary to the traditional strengthening route by adding multiple & high-dosage alloying elements, we here explored extremely compositional and phase-constituent “simplification” in rare earth (RE) containing biodegradable magnesium alloys for better biocompatibility. An ultra-lean Mg-0.1Pr alloy with a multiscale microstructure has been developed through casting and extrusion, which showed well-balanced performances that match the commercial Mg-based orthopedic products. Compared to the first clinically approved WE43 magnesium alloy, the complex RE addition (7 wt.%) in WE43 is simplified into one single RE (0.1 wt.%) with its content having a 70-fold reduction in the newly developed alloy, while without impairing mechanical properties (tensile strength: 285.6 MPa). This also leads to a mild degradation rate, a good cell & tissue compatibility and osteogenic capacity both in vitro and in vivo . The simplified Mg-0.1Pr alloy exhibits excellent local and systemic biocompatibility in the femoral condyle of rats during a 16-month long-term follow-up, with this period approximately covering the entire life cycle of the implant. In addition, the Mg-0.1Pr alloy exhibits a significantly lowered RE transfer and accumulation in rats compared to other Mg-RE alloys, which possibly alleviates the RE metabolic burden to main organs. Pr is neither accumulated in the corrosion product layer nor in the surrounding bones. This work provides a new solution to maintain the high performance of Mg-RE alloys with extremely compositional “plainification”, which should further benefit for the safety and reliability of RE-strengthened biodegradable metals in the long-term.
研究领域:
材料科学
·
生物医学工程
·
冶金学
·
生物材料
·
生物相容性
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Yuan Zhang,Xuelin Zhang,Jiupai Ni,Chengsheng Ni
The use of identical electrodes for both the cathode and the anode in a symmetrical solid oxide fuel cell (SSOFC) can simplify the preparation process and increase the durability of the cell, but it is also demanding on the properties of the electrode including stability, electric conductivity, and electrocatalysis. The doping of variable-valence Mn4+/3+2+ on the B site of stable SrTiO3 is explored in this study as both the cathode and the anode for an SSOFC. Though the limit of Mn doping in SrTiO3 is generally low, the additional Pr3+/4+ donor on the Sr site of SrTi0.5Mn0.5O3 was found to enhance the structure stability, electric conductivity, and electrocatalysis. The cell with Pr0.5Sr0.5Ti0.5Mn0.5O3 electrodes excels under H2, propane, or CH4/H2 fuel, providing the cocatalyst was infiltrated on the anode side. The polarization resistance value of Pr0.5Sr0.5Ti0.5Mn0.5O3 was 0.27 Ω·cm2 as the cathode and 0.33 Ω·cm2 for the SSOFC using H2 fuel. The performance under CH4/H2 fuel can be boosted to above 0.9 W cm–2 if Ni/ceria was loaded onto the anode to enhance the methane reforming. This work contributes to a perovskite anode with high Mn doping in SrTiO3 for application in SSOFC for natural gas with renewable H2 injection.
研究领域:
材料科学
·
电化学
·
能源工程
·
燃料电池
✓ 已验证
DOI
高影响因子
FOOD AND CHEMICAL TOXICOLOGY
·
2020
·
IF 4.679
Chunlei Zhu,Fengru Liu,Yunlong Wei,Fan Zhang,Ting Pan,Yingwang Ye,Yizhong Shen
Having reported that rare earth elements displayed potential toxicity i n vivo , often be found in soil, plants and etc. , which might be easily chelated with the natural functional molecule rutin to form rutin metal complexes, ultimately entering the human body by means of food chain . However, few reports paid the attention on the toxicology of the complexes consisting of rutin with rare earth ions. Here, we focused on the potential toxicity by probing the site-selective binding of the rutin-rare earth ions complexes to human serum albumin (HSA). As a proof-of-concept, we selected Pr 3+ as the representative to conjugate with rutin to form rutin-Pr(III) complex, which was further applied to interact with HSA in aqueous solution. The results exhibited that the rutin-Pr(III) complex primary bound to the hydrophobic cavity at site II (subdomain IIIA) of HSA through hydrogen bonding and van der Waals force . Through the thermomechanical analysis, we found this binding process was spontaneous because of the negative Δ G. We believe that this work may offer a new insight into understanding the physiological effects ( e.g. toxicology) of rutin and rare earth ions, which could be helpful to guide their rational use in the agriculture and environment-related industries.
研究领域:
毒理学
·
生物化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Precision Engineering and Manufacturing-Green Technology
·
2023
·Vol. 11
·期 2
·449-461
·
IF 4.2
Yang Xinlei,Yang Fan,Afzal Muhammad,Sun Wanli,Kim Jung-Sik
La/Pr co-doped ceria (LCP) is processed to fabricate low-temperature ceramic fuel cell based on industrial-grade rare-earth carbonate electrolyte that is reached above a maximum power density of 750 mW/cm 2 at 520 °C. The charge carriers are investigated through LCP fuel cell having symmetric NCAL (Ni 0.8 Co 0.15 Al 0.05 LiO 2-δ ) electrodes using proton conductor BCZY (BaCe 0.7 Zr 0.1 Y 0.2 O 3-δ ) as a blocking layer and are found protons that dominate during the cell operation. The results of associated characterizations for HCC (hydrogen concentration cell) and the OCC (oxygen concentration cell) reveal that LCP material is mixed conductor of both protons and oxygen ions simultaneously. Transmission electron microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) analysis before and after the electrochemical testing of the cell are performed which show an amorphous layer of LiOH/Li 2 CO 3 mixture that is formed after the tests on the surface of LCP structure. Conceptually, it looks that LiOH/Li 2 CO 3 mixture in molten state in the interface region of two-phase material promotes the proton conduction through LCP electrolyte, with negligible oxygen ion conduction.
研究领域:
能源材料
·
固态电化学
·
燃料电池
·
材料科学
·
纳米技术
·
无机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2016
·
IF 2.857
Chun Liu,Fenfen Cheng,Yingen Sun,Hongyu Ma,Xiaoquan Yang
An alkaline isoform of the PR-5 protein (designated GmOLPc) has been purified from soybean hulls and identified by MALDI-TOF/TOF-MS. GmOLPc effectively inhibited in vitro the growth of Phytophthora soja spore and Pseudomonas syringae pv glycinea. The antimicrobial activity of GmOLPc should be mainly ascribed to its high binding affinity with vesicles composed of DPPG, (1,3)-β-d-glucans, and weak endo-(1,3)-β-d-glucanase activity. From the 3D models, predicted by the homology modeling, GmOLPc contains an extended negatively charged cleft. The cleft was proved to be a prerequisite for endo-(1,3)-β-d-glucanase activity. Molecular docking revealed that the positioning of linear (1,3)-β-d-glucans in the cleft of GmOLPc allowed an interaction with Glu83 and Asp101 that were responsible for the hydrolytic cleavage of glucans. Interactions of GmOLPc with model membranes indicated that GmOLPc possesses good surface activity which could contribute to its antimicrobial activity, as proved by the behavior of perturbing the integrity of membranes through surface hydrophobic amino acid residues (Phe89 and Phe94).
研究领域:
植物病理学
·
分子生物学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Minzhi Ma,Zeai Huang,Lina Li,Wenda Zhang,Rui Guo,Ruiyang Zhang,Wenjun Fa,Chunqiu Han,Yuehan Cao,Shan Yu,Ying Zhou
The performance of photocatalytic reduction CO 2 to CH 3 OH is intimately tied to the photogenerated electron density of the active center, because CH 3 OH formation involves a 6-electron transfer process. However, the random migration of photocarriers in the photocatalysts is severely not conducive to the directional delivery and enrichment of photogenerated electrons to active sites, leading to poor photocatalytic activity for CO 2 to CH 3 OH. Herein, we reported a coordination environment engineered Pr single-atom catalyst for boosting the photogenerated electron density of the active sites, achieving the high-efficiency photoreduction of CO 2 to CH 3 OH. The carbon nitride (CN) supported Pr single-atom with oxygen coordination was designed via a three-step pyrolysis process . Then, the engineered oxygen coordination configuration for the Pr single-atom (Pr 1 -N 4 O 2 ) was successfully achieved. Importantly, this Pr 1 -N 4 O 2 sites can induce photogenerated electrons more easily to accumulate on the Pr atom as compared to the reference catalyst of the Pr atom without oxygen coordination (Pr 1 -N 6 ). Moreover, the formed atomically dispersed Pr 1 -N 4 O 2 active centers with ultra-high Pr loading (21.05 wt%) can promote CO 2 adsorption and activation, and provide a high density of active sites for CO 2 photoreduction. As a result, the optimized Pr 1 -N 4 O 2 /CN exhibited a boosted photoreduction of CO 2 to CH 3 OH activity (511.1 μmol g −1 h −1 ), which was up to 28.9 and 1.9 times higher than those of CN (17.7 μmol g −1 h −1 ) and Pr 1 -N 6 /CN (274.1 μmol g −1 h −1 ), and preferable to most reported work under similar catalytic conditions. Our findings can provide a fresh prospect for developing innovative SACs to enhance the photoreduction of CO 2 to CH 3 OH activity.
研究领域:
材料科学
·
催化
·
环境化学
·
光化学
✓ 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）