Catalysis Science & Technology
·
2024
·
IF 4.4
Shan Hu,Yunfei Gao,Lu Ding,Xueli Chen,Weitong Pan,Fuchen Wang
Hydroformylation is an important reaction for aldehyde synthesis and requires ethylene and syngas (CO + H2) with the feedstocks. While these feedstocks are typically synthesized separately, it would be highly desirable to directly convert abundant ethane into ethylene and syngas in a single step. In this work, we loaded B2O3 onto perovskite La0.8Sr0.2FeO3 (LSF) and formed a core–shell structured catalyst, with B2O3 and Sr3B2O6 being the shell and LSF being the core. The shell structure can substantially inhibit deep oxidation of ethane into CO2 and the optimized La0.8Sr0.2FeO3@20B2O3 can achieve 69.2% ethane conversion and 88.8% ethylene + syngas selectivity at 700 °C with good stability, with a ratio of CO/H2 close to 1 : 1. The effects of reaction temperature, space velocity, B2O3 loading, and La/Sr were also investigated. This catalyst marks a promising progress for the direct oxidation of ethane and has good potential for industrial applications.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2023
·
IF 3.5
Mingjun Zhao,Yiting Tao,Panting Wang,Ting Wu,Danping Chen,Wei Chen
This study discovered that a transparent BaF 2 -B 2 O 3 glass system without rare-earth ions prepared under CO-reducing atmosphere exhibited orange-red self-luminescence under near-UV light, generating broadband luminescence from 550∼850 nm centered at 650 nm under broadband light excitation at about 397 nm. Based on the results of spectra, electron spin resonance, Raman, and X-ray photoelectron spectroscopy, it is proposed that the luminescence phenomenon is due to the s→p transition of B 2+ generated inside the glass under the reducing atmosphere. This new luminescent glass has the potential to be an orange-red luminescent material excited by a light-emitting diode.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2020
·Vol. 11
·期 1
·1-7
·
IF 12.121
Tian Jinshu,Tan Jiangqiao,Zhang Zhaoxia,Han Peijie,Yin Min,Wan Shaolong,Lin Jingdong,Wang Shuai,Wang Yong
Direct oxidation of methane to value-added C 1 chemicals (e.g. HCHO and CO) provides a promising way to utilize natural gas sources under relatively mild conditions. Such conversions remain, however, a key selectivity challenge, resulting from the facile formation of undesired fully-oxidized CO 2 . Here we show that B 2 O 3 -based catalysts are selective in the direct conversion of methane to HCHO and CO (~94% selectivity with a HCHO/CO ratio of ~1 at 6% conversion) and highly stable (over 100 hour time-on-stream operation) conducted in a fixed-bed reactor (550 °C, 100 kPa, space velocity 4650 mL g cat −1 h −1 ). Combined catalyst characterization, kinetic studies, and isotopic labeling experiments unveil that molecular O 2 bonded to tri-coordinated BO 3 centers on B 2 O 3 surfaces acts as a judicious oxidant for methane activation with mitigated CO 2 formation, even at high O 2 /CH 4 ratios of the feed. These findings shed light on the great potential of designing innovative catalytic processes for the direct conversion of alkanes to fuels/chemicals.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2013
·
IF 2.39
C.X. Chen,S.P. Wu,Y.X. Fan
Orthorhombic Mg 2 GeO 4 ceramics were synthesized by solid-state reaction method. When stoichiometric compositions were employed, the phase transition produced under low temperature and pure orthorhombic Mg 2 GeO 4 phase appeared at 1000 °C. B 2 O 3 was employed as sintering aid to lower the sintering temperature of Mg 2 GeO 4 ceramics and improve their relative densities. The B 2 O 3 -doped Mg 2 GeO 4 ceramics have a low sintering temperature of 1250 °C and a small negative τ f value. Microwave dielectric properties of B 2 O 3 -doped Mg 2 GeO 4 ceramics were: ε r = 6.76, Q × f = 95,000 GHz and τ f = −28.7 ppm/°C. They could be considered as promising candidate materials for microwave/millimeter-wave devices.
研究领域:
材料科学
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2022
·Vol. 20
·期 2
·906-916
·
IF 2.328
Lingyu Jia,Peigang He,Dechang Jia,Jingkun Yuan,Delong Cai,Daxin Li,Xiaoming Duan,Zhihua Yang,Yu Zhou
Sr-containing ceramic products produced from geopolymer, (Na, Sr)-GP, have been reported as excellent candidate materials for the immobilization of radionuclide 90Sr, despite sintering temperature at 1200°C. In this work, the product possessing the best immobilization performance (leaching rate of 1.29% for Sr 2+ ) can be produced at 1000°C in the method of liquid-phase sintering via the addition of fluxing agent B 2 O 3 at 2.0 wt% in the geopolymer precursor. The mechanical properties of the geopolymer precursor (Na, Sr)-GP were also enhanced via the promotion role of B 2 O 3 to geopolymerization. It was revealed that the overall anti-leaching ability of the Sr-containing ceramic product not only depends on the microstructure of the loading substrate but also can be affected by the chemical state of radioactive strontium retention in the loading matrix.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2024
·
IF 2.8
Yang Li,Fen Luo,Jiahong Wang,Yu Gao,Gangchuan Ji,Xirui Lu
This study used a ternary Na 2 O-B 2 O 3 -SiO 2 matrix to simulate the immobilization of complex TRPO waste. The study investigated the relationship between the solidified bodies with different TRPO waste contents and their solid solubility, FT-IR, Vickers hardness, and density. The study found that the maximum amount of TRPO waste that can be immobilized in the Na 2 O-B 2 O 3 -SiO 2 matrix was 20 wt .%. When the TRPO waste content ranged from 5-15 wt .%, it was primarily immobilized in the glassy phase. When the TRPO waste content exceeded 20 wt .%, the crystalline phases NdBO 3 and Na 3 Nd(BO 3 ) 2 , which contain the main waste element Nd appeared. Samples containing 20 wt .% TRPO waste resulted in leaching of 10 -6 g·m -2 ·d -1 . The presence of NdBO 3 and Na 3 Nd(BO 3 ) 2 crystals resulted in a decrease in the Vickers hardness and density of the samples. The highest values for Vickers hardness and density were 6.77 GPa and 2.7 g -1 cm -3 , respectively. The borosilicate matrix utilized in this study has proven to be an effective immobilization of complex TRPO wastes and holds promise as a treatment matrix for TRPO wastes.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Yu Tang,Zhiwei Luo,Taoyong Liu,Piao Liu,Zhuo Li,Anxian Lu
Li 6.5 La 3 Zr 1.5 Nb 0.5 O 12 (LLZN) garnet-type structure was synthesized at low temperature with B 2 O 3 addition by solid state reaction method. The effects of B 2 O 3 content on the formation, microstructure, ionic conductivity and activation energy of the LLZN solid electrolytes have been investigated by X-Ray diffraction (XRD), scanning electron microscopy (SEM) and alternate current (AC) impedance spectroscopy . The cubic LLZN phase was obtained after calcining at 850 °C for 6 h and no phase evolution was observed after sintering at 1100 °C for 6 h. The relative density and lithium ion conductivity increased first and then decreased with increasing B 2 O 3 content, reaching the maximum value of 92.4% and 1.86×10 −4 S cm −1 respectively in the sample with 1.4 wt% B 2 O 3 . By contrast, the activation energy reached a minimum value of ~31.5 kJ mol −1 .
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2021
·
IF 3.995
Panpan Xu,Yupeng Wang,Wentao Hao,Li Sun,Ensi Cao,Yongjia Zhang
TiO 2 ceramics co-doped with In and Nb exhibit unusual large dielectric-permittivity phenomena, but their sintering temperature is essentially higher than 1400 °C and the holding time is usually longer than 5 h, which is very uneconomical for industrial production and practical applications. Therefore, to maintain the relatively good dielectric properties of In and Nb co-doped TiO 2 ceramics and reduce the sintering temperature to about 1300 °C, B 2 O 3 , was added as a sintering aid to prepare B 2 O 3 /(In 0.5 Nb 0.5 ) 0.05 Ti 0.95 O 2 ceramics in this paper. The crystalline structures, microstructures, and electrical properties were investigated and discussed. The results showed that the sintering temperature of B 2 O 3 /(In 0.5 Nb 0.5 ) 0.05 Ti 0.95 O 2 ceramics indeed prominently decreased, but their dielectric loss was relatively large, possibly caused by the pores left following B 2 O 3 volatilization.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2024
·Vol. 130
·期 3
·203
·
IF 2.5
Xu Yingying,Xia Siyi,Zhang Yingjiu,Song Hongzhang,Liu Shaohui,Hao Haoshan
In this study, ceramic samples of Bi 2 Sr 2 Co 2 O y + v wt% B 2 O 3 ( v = 0.0, 0.1, 0.2, 0.3, 0.4) were synthesized using the solid state reaction method, and the influence of B 2 O 3 additive on their microstructure and thermoelectric properties were investigated. On one hand, the B 2 O 3 additive acted as a sintering aid, enhancing carrier mobility. On the other hand, B 2 O 3 dispersion served as a nano-second-phase, increasing hetero-interfaces and strengthen phonon scattering, thereby effectively suppressing lattice thermal conductivity. By dual optimization of both electric and thermal transport performance, the Bi 2 Sr 2 Co 2 O y + 0.3 wt% B 2 O 3 sample achieved a high ZT value (thermoelectric figure of merit) of 0.31 at 923 K, which was improved by approximately 33% compared with the pristine Bi 2 Sr 2 Co 2 O y sample.
研究领域:
材料科学
·
凝聚态物理
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无机非金属材料
·
热电材料
✓ 已验证
DOI
高影响因子
Transactions of the Indian Ceramic Society
·
2024
·
IF 1.5
Jialu Li,Yuanbing Li,Shujing Li,Kun Xiang
BPO4-B2O3 composite additive enhanced silica ceramics were successfully prepared by solid phase sintering. The effects of BPO4-B2O3 addition and sintering temperature on the microstructure and phase composition and mechanical properties of silica ceramics were analysed by scanning electron microscopy and X-ray diffraction techniques. The results showed that at 1200°-1400°C, BPO4-B2O3 composite additive formed a glass phase in the sample, filled the pores, and improved the sintering densification of the sample. In addition, the addition of 9 wt% BPO4-B2O3 successfully inhibited the crystallization of fused silica, which significantly improved the mechanical strength of silica ceramics. After sintering at 1200°C for 3 h, the apparent porosity of silica ceramics with 9 wt% BPO4-B2O3 was only 1.33%, and the cold modulus of rupture reached a maximum of 60.99 MPa, which was about 35 times that of pure silica ceramics. It is shown that adding BPO4-B2O3 composite additive provides a feasible method for preparing silica ceramics with good mechanical properties.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2024
·
IF 3.2
Bo Wang,Zihao Pan,Ziyan Zhao,Bo Zhou,Xuejian Liu,Zhengren Huang,Yan Liu
In this paper, we designed two series of the ZnO-B 2 O 3 -SiO 2 (ZBS) glass to explore their applicability for joining AlN ceramic. The density, flexural strength, structure, characteristic temperature, coefficient of thermal expansion (CTE) and crystallization behavior of the ZBS glass with varying ZnO and B 2 O 3 content were systematically studied. The results show that as B 2 O 3 content increase, the glass network is disrupted with the transition from three-dimensional shelf-like structure [BO 4 ] to two-dimensional layers [BO 3 ], increasing the number of the broken bonds, while an increase in ZnO results in a more compact glass network structure. We also found that both glass transition temperature (T g ) and softening temperature (T S ) exhibit a declining trend with the increase in B 2 O 3 and ZnO. Zn 2 SiO 4 and ZnAl 2 O 4 , began to precipitate after heat treatments in all the samples except 60ZnO-30B 2 O 3 –10SiO 2 (abbreviated as B30), where the diffraction peaks do not appear in Zn 2 SiO 4 but in Zn 4 B 6 O 13 . Notably, Zn 2 SiO 4 is the main phase for most samples while the main phase of B30 sample is ZnAl 2 O 4 . The CTE increases from 4.6 to 5.03 (× 10 –6 / °C) and 4.23 to 4.73 (× 10 –6 / °C) with an increase of B 2 O 3 and ZnO content, respectively. Among these, the CTE of B30 sample is compatible with that of AlN ceramic substrate. The optimal shear strength, 60.32±10.26 MPa, was achieved with B30 samples at 750 °C. The high strength was attributed to the interfacial reaction that leads to strong chemical bonding and the uniform distribution of the ZnAl 2 O 4 in the interlayer, which reinforces the strength of the interlayer itself.
研究领域:
材料科学
·
无机非金属材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Junping Shi,Lielin Wang,Hua Xie,Shidi Yao,Xiuqi Pu,Zhu Liu,Xiaojiang Chen,Yun Ding
Highly reactive fission product cesium may volatilize at high temperatures. PbO–B 2 O 3 –ZnO glass with low melting temperature and excellent chemical durability can be used as a potential matrix for immobilizing Cs. In this work, five PbO–B 2 O 3 –ZnO glasses with different contents of Pb were synthesized via a melt-quenching process. These specimens were characterized with XRD , Raman, DTA and viscosity measurements . The results showed that the melting temperature decreases, viscosity decreases and structural polymerization increases with increasing lead content. Cs-doped 35PbO–60B 2 O 3 –5ZnO glasses were synthesized at low temperatures. XRD results revealed the amorphous nature of the glass solidified bodies. EDS and ICP-MS studies confirmed that Cs is retained in the glass. Clear vitrified waste products containing up to 13.6 wt% Cs were obtained. The chemical durability of the samples was evaluated via PCT-A and MCC-1 method. For the glass solidified body comprising a Cs/matrix ratio of 0.136, the leaching rate of Cs was 1.6 × 10 −1 g m −2 d −1 from the PCT test, which indicates that it has a good chemical stability. 35PbO–60B 2 O 3 –5ZnO glass was expected to be a suitable matrix for Cs immobilization.
研究领域:
材料科学
·
核废料管理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）