Crystals
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2022
·Vol. 12
·期 10
·1339
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IF 2.67
Hui Han,Ying-Ying Wang,Xing-Chao Yu,Yan-Na Ma,Xuenian Chen
Alkali metal (M = Na, K) salts of the [CB11H12]−anion have attracted increasing attention in many fields such as catalysis and all-solid-state batteries. However, tedious and low-yielding synthetic methods have seriously limited their application in these fields. We developed a facile method for the direct synthesis of the unsolvated potassium and sodium salts of the [CB11H12]−anion in 66% and 68% yields, respectively, by reactions of Na[B11H14] with NaH/NaHMDS (sodium bis(trimethylsilyl)amide), CF3SiMe3in THF and K[B11H14] with KH, CF3SiMe3in DME. This method avoids the exchange of cation and significantly simplifies the reaction setup, thus enabling convenient large-scale synthesis. It is believed that this method will support further application of Na[CB11H12] and K[CB11H12] as solid electrolytes for an all-solid-state battery.Keywords:Na[CB11H12];K[CB11H12];Na[B11H14];K[B11H14];one-pot synthesis
研究领域:
材料化学
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电化学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2023
·
IF 2.6
Tingting Zhou,Xueli Huang,Baharguli Hadeerbieke,Fangning Yan,Xueying Wang,Qinglong Luo
The phase diagram can guide the comprehensive utilization of salt lake brine, particularly lithium extraction. In this paper, the study on phase equilibria of the quinary system Li+, Na+, K+, Mg2+//Cl––H2O saturated with NaCl·2H2O and its subsystem Li+, Na+, Mg2+//Cl––H2O at 258.15 K were carried out using the isothermal dissolution equilibrium method. Based on the experimental data, equilibrium diagrams for stable phases were plotted. For the equilibrium diagram of the quaternary system Li+, Na+, Mg2+//Cl––H2O at 258.15 K, there are two invariant points, five univariant curves, and four crystallization fields. The quinary system Li+, Na+, K+, Mg2+//Cl––H2O saturated with NaCl·2H2O at 258.15 K contains three invariant points, seven univariant curves, and five crystallization fields. Comparing the phase diagram of the system at 258.15 K to that at 298.15 K reveals that, except KCl, all crystallization zones have decreased, and LiCl·MgCl2·7H2O has the smallest crystallization zone compared to the other salts in the systems. This fundamental research could be valuable for promoting comprehensive utilization of the lithium-containing salt lake brine.
研究领域:
化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2015
·Vol. 26
·期 9
·6776-6780
·
IF 1.569
Cao Renping,Xu Haidong,Peng Dedong,Gou Qingdong,Zhou Shenlin,Liu Pan,Yu Xiaoguang
BaWO 4 :Sm 3+ , Mo 6+ /K + phosphors are synthesized by a high temperature solid-state reaction method in air. The very strong emission bands peaking at ~600 and 644 nm and the strongest excitation band peaking at ~403 nm are assigned to the 4 G 5/2 → 6 H J (J = 7/2 and 9/2) and 6 H 5 / 2 → 4 F 7 / 2 transitions of Sm 3+ ion, respectively. The optimal Sm 3+ doping concentration is ~5 mol%. Emission intensity of BaWO 4 :Sm 3+ phosphor is increased more than twice owing to charge compensation when the K + ion is codoped as charge compensator, however, Mo 6+ ions is small influence to its emission intensity. The energy transfers and luminous mechanism are explained by using energy level diagrams of WO 4
2− group and Sm 3+ ion. Lifetimes of Ba 0.925 WO 4 :0.05Sm 3+ , Ba 0.925 W 0.9 Mo 0.1 O 4 :0.05Sm 3+ , and Ba 0.9 K 0.05 WO 4 :0.05Sm 3+ phosphors with excitation 403 nm are about 0.933, 0.882, and 0.693 ms, respectively. The experiment results indicate that BaWO 4 :Sm 3+ , Mo 6+ /K + phosphors will be a potential red phosphor candidate for white LEDs based on near UV (~403 nm) LED chip and research contents are useful to improve luminescence properties of Sm 3+ -doped phosphors.
研究领域:
材料科学
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光学
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产品关联
DOI
高影响因子
Molecular Catalysis
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2022
·
IF 5.089
Chengcheng Yi,Jia Fang,Ping Pu,Yi Yang,Zong Chen,Zinong Zuo,Zhiqiang Han
A series of K-Ce catalysts with different K/(K+Ce) molar ratios are successfully prepared by hydrothermal method, to optimize catalyst diesel particlate filter (CDPF) regeneration efficiency of soot elimination. The K-Ce catalyst is an excellent promoter for soot combustion by thermogravimetric analysis (TGA), and the KC-0.2 catalyst has the best catalytic activity because proper K ions lead to more oxygen vacancies and improve contact efficiency with soot. This result corresponds well to characterization analysis, such as XRD, SEM and XPS. In a 10%O 2 /90%N 2 atmosphere, the KC-0.2 has the highest average mass loss rate ( W mean ), maximum mass loss rate ( W max ) and combustion stability index ( R w ). The weight ratios of the soot/KC-0.2 mixture are less than 1:10, making catalytic oxidation easier for the soot. Thermal aging in static air at 600 °C is used to investigate the catalytic stability of KC-0.2, and the TGA results show that KC-0.2 has good stability at temperatures lower than 600 °C. Compare to KC-0.2, the KC-0.2 based mixed catalyst with ZrO 2 participation is further prepared by mechanical method and has better catalytic activity because the presence of Zr enhances redox surface sites of catalyst. This facilitates the exploration of novel catalysts through combinatorial catalysis.
研究领域:
环境科学
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催化化学
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产品关联
DOI
高影响因子
EUROPEAN JOURNAL OF PHARMACOLOGY
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2017
·
IF 2.896
Cheng-yuan Li,Mei Su,Yun-yi Yan,Lin Zhou,Lu-yao Ao,Wei-rong Fang,Yun-man Li
1-(5-(1H-indol-5-yl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl)-N-methylmethanamine (KFP-H008)，a novel and potent potassium-competitive acid blocker for the treatment of acid secretion related diseases, has not been reported previously. In this study, we demonstrated that KFP-H008 inhibits basal acid secretion, 2-deoxy- D -glucose- (2DG-) stimulated gastric acid secretion in rats. KFP-H008 blocked histamine-stimulated acid secretion in rats and heidenhain pouch dogs and reversed acid output in isolated gastric perfusion under histamine stimulation. In all the animal experiments, KFP-H008 exerted a more effective, potent and longer-lasting inhibitory action in comparison with lansoprazole , a proton pump inhibitor (PPI) commonly used in clinic. KFP-H008 inhibited H + -K + -ATPase activity both at pH 6.5 and pH 7.5, and was unaffected by pH. The inhibitory action was reversible and was achieved in a K + -competitive manner. Furthermore, KFP-H008 did not affect Na + -K + -ATPase activity, thus exhibiting high selectivity, which is different from PPIs. In all, KFP-H008, a novel potassium-competitive acid blocker, may provide new option for the patients with acid-related diseases and provide longer-lasting inhibitory action than drugs commonly used in clinical treatment.
研究领域:
药理学
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胃肠病学
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药物开发
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产品关联
DOI
PubMed
高影响因子
Nutrients
·
2024
·Vol. 16
·期 19
·3351
·
IF 4.8
Haiyan Wang,Zhenyu Yang,Shuxia Wang,Huwei Wu,Xuehong Pang,Yichun Hu,Xiaoguang Yang
Objectives: This study sought to understand the levels of vitamin K in the mature milk of Chinese lactating mothers, thereby providing a foundation for the development of appropriate intake (AI) of vitamin K for infants aged 0–5 months. Methods: Five hundred healthy lactating mothers were selected from the mature milk bank established by the Chinese Maternal and Infant Nutrition and Health Cohort by using a simple random sample procedure. Relevant information about lactating mothers and their infants was obtained by a questionnaire survey. Vitamin K1 and vitamin K2 (MK-4 and MK-7) in mature milk were determined by liquid chromatography–tandem mass spectrometry. Results: The total concentration of vitamin K in mature milk was 4.50 (2.85–6.33) ng/mL. The concentrations of vitamin K1, vitamin K2, MK-4, and MK-7 were 2.81 (1.66–4.39) ng/mL, 1.37 (0.75–2.11) ng/mL, 1.20 (0.58–1.97) ng/mL, and 0.13 (0.08–0.19) ng/mL, respectively. The concentration of vitamin K1 was highest and the concentration of MK-7 was lowest. The concentrations of vitamin K2 and MK-4 in mature milk from the south were significantly higher than those in mature milk from the north. The total vitamin K, vitamin K2, and MK-4 concentrations in mature milk of lactating mothers residing in urban areas were higher than those in rural areas. There was a tendency for the concentration of total vitamin K and vitamin K1 to increase with the mother’s age. Moreover, the concentration of MK-4 in mature milk was highest in summer, followed by spring and winter. The levels of vitamin K1 and MK-4 in mature milk were found to be affected by lactation stage; they were highest at 91–120 days and lowest at 31–60 days. Conclusions: Based on the concentration of vitamin K in mature milk found in this study, it is recommended that the appropriate intake of VK for Chinese infants aged 0–5 months is 3.49 μg/d (2.18 μg/d for VK1 and 1.06 μg/d for VK2).
研究领域:
营养学
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儿科医学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2016
·
IF 1.835
Jianfeng Hao,Wenge Yang,Hongjie Li,Shimin Fan,Wangdan Zhao,Yonghong Hu
We focus on the solubility of 4-methylsulfonylacetophenone. A gravimetric method was taken to measure the solubility of 4-methylsulfonylacetophenone in n-hexane, ethyl acetate, methanol, ethanol, n-propyl alcohol, n-butyl alcohol, ethylene glycol, cyclohexane, isobutyl alcohol, and (ethyl acetate + n-hexane) binary solvent mixtures from 278.15 K to 328.15 K under atmospheric pressure. Its corresponding (solid + liquid) equilibrium results will provide essential support for further theoretical studies. The solubility of 4-methylsulfonylacetophenone in nine pure solvents were correlated with λh and Apelblat models, while 4-methylsulfonylacetophenone in (ethyl acetate + n-hexane) binary solvent mixtures were correlated with the Apelblat and CNIBS/R–K models. The Apelblat model was proven to be the best-fit model for correlating the solubility of both pure solvents and binary solvents mixtures from the analysis of the STATISTIC.
研究领域:
化学
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物理化学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
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2022
·Vol. 46
·期 11
·15376-15386
·
IF 4.672
Tianle Li,Siddig Abuelgasim,Wenju Wang,Yupeng Xiao,Chenlong Liu,Yaoyao Ying,Dong Liu
Summary Soot particulate emitting from diesel engines are serious to both human health and environment. Efficient catalyst is vital in diesel particulate filter technology to decrease soot oxidation temperature. Cu 1−x K x Fe 2 O 4 (x = 0, 0.05, 0.1, and 0.15) catalysts are synthesized and analyzed with XRD, Raman, BET, SEM, TEM, TG, EDS, XPS, catalytic activity tests, and kinetic analysis. The results suggests that many factors affect the catalytic activity, and the contents of oxygen vacancies are dominant. A large amount of oxygen vacancies which facilitate to the soot oxidation are created with the assistance of K + , and they increase with the increasing doping contents. Excessive surface concentration of K + may lead to the partially covering of active sites of the catalysts. Therefore, Cu 0.9 K 0.1 Fe 2 O 4 catalyst exhibits the best catalytic activity in soot oxidation, which decreases the T max of soot by 279°C. This decrease makes it highly promising for application in diesel particulate filter.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Lingyu Jia,Tingting Yang,Zixu Chen,Xingqi Liao,Peigang He,Dechang Jia,Xiaoming Duan,Zhihua Yang,Yu Zhou
In this work, we utilized an in-situ chemical synthesis method to fabricate a Fe 3 O 4 /K-geopolymer (KGP) composite to be applied in a microwave absorbent field. This material, as a type of ceramic precursor, is highly expected to be a 3D printing material to prepare microwave absorbing components with complex shapes. The investigation results demonstrate that the material possesses a large effective microwave absorbing bandwidth of 3.7 GHz with the minimum reflection loss reducing to −12.2 dB when the generated Fe 3 O 4 percent reaches 12 wt% in the KGP composite. This microwave absorbent performance can be attributed to a synergistic effect between the eddy current loss caused by the improved electrical conductivity of magnetic nanoparticles and the interfacial polarization effect from the geopolymer matrix and magnetic medium interface. Also, we used direct ink writing technology to print two-dimensional components with desirable patterns. Thickness-dependent wave absorption evaluation results confirmed a maximum reflection loss of −25.9 dB at 15.2 Hz was obtained from the printed sample containing 9.0 wt% Fe 3 O 4 for a layer thickness of 10 mm, indicating that wave consumption effectiveness was determined by porous microstructures, magnetic loss of Fe 3 O 4 nanoparticles as well as suitable impedance matching. The preparation method and synthesized material pave the way for integrated manufacturing of 3D printing components with microwave absorbing performance.
研究领域:
材料科学
·
电磁学
·
制造工程
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DOI
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Ruimei Fang,Qiuyu Feng,Haibao Huang,Jian Ji,Miao He,Yujie Zhan,Biyuan Liu,Dennis Y.C. Leung
δ -MnO 2 was prepared via a facile in-situ redox reaction and used for catalytic oxidation of HCHO, a major indoor air pollutant. The washing treatment during catalyst preparation could impose great effect on content of K + and catalytic activity. δ -MnO 2 catalyst without washing treatment contains the highest content of K + ion and exhibits the best catalytic activity among various δ -MnO 2 samples. The HCHO removal efficiency keeps at 100% for first 600 min. The δ -MnO 2 samples were characterized by advanced technologies including XRD, Raman, XPS, TPR, TPD and in-situ DRIFTS. The XPS results indicates that K + ions increases the AOS value of Mn and the ratio of surface-adsorbed oxygen over δ -MnO 2 . The content of K + ions improves the amount and redox ability of surface mobile oxygen species, enhancing catalytic oxidation of HCHO.
研究领域:
环境科学
·
催化材料
✓ 已验证
DOI
高影响因子
MACROMOLECULES
·
2023
·
IF 5.5
Jian Lu,Yu Zhang,Jing Li,Meifang Fu,Guoxiang Zou,Shinji Ando,Yongbing Zhuang
The correlations between the molecular structures of four Tröger’s base (TB)-based polyimides (PIs) and two non-TB containing analogues and physical properties including thermal conductivity (λ) and dielectric properties both at low and high frequencies were investigated in detail. The TB-based PI films exhibited low dielectric constants (Dk = 2.25–2.80) at 10 GHz. They possessed much lower λ values (0.035–0.145 W/mK) compared to the commercial PI Kapton (0.240 W/mK). The influences of incorporating TB units into chain backbones on aggregation structures and physical properties of PIs were identified. Incorporating TB units into chain backbones effectively reduced the degree of chain orientation and increased fractional free volume, leading to both low Dk and low λ values for the resulting PI films. Also, introducing TB units enhanced molecular weights, toughness, and glass-transition temperature (Tg) of the resulting PIs. Therefore, the TB-based PIs can be promising heat-insulating and low-k dielectric materials.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2023
·
IF 4.6
Dou Zhang,Bo-hui Li,Yi-lei Li,Jun Zhao,Xiao-jing Wang,Fa-tang Li
The efficient conversion of CO 2 to carbon-neural fuels by photocatalysts can effectively address the increasingly prominent challenges of environmental pollution and energy shortage. TiO 2 is considered a promising photocatalyst. However, its disadvantages, such as poor adsorption of CO 2 and low carrier separation efficiency, inhibit its performance and selectivity in photocatalytic CO 2 reduction. Herein, K + -modified anatase TiO 2 ultrathin nanosheet photocatalysts were obtained via a reverse etching method using K 2 Ti 8 O 17 as the precursor. The selectivity of the optimized photocatalyst for methane was 96.02% in a gas–solid system without additives, with an excellent photocatalytic rate of 42.3 μmol·g −1 ·h −1 , which was 3.39 times higher than that of P25. The effects of K + on photocatalytic behaviors and the selectivity of CH 4 was systematically investigated. The test results showed that during treatment with formic acid, a large amount of K + from the layered K 2 Ti 8 O 17 were removed and the original structure was destroyed. Therefore, highly dispersed TiO 2 nanosheets were obtained, with a small amount of K + remaining on the TiO 2 surface. The well-defined rectangular shapes of TiO 2 reduce the transmission distance of photogenerated carriers, whereas the presence of K + increase the chemisorption of CO 2 molecules, thereby activating CO 2 , promoting the conversion of bridge *CO to -CHO, and increasing CH 4 production. This study provides insightful references for the preparation and modification of traditional photocatalysts for photocatalytic CO 2 reduction reactions.
研究领域:
材料科学
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环境科学
·
能源科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）