CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Dong Yi,Jiawei Fu,Fenzhong Long,Jin Han,Fangui Meng,Xinmin Zhang
To improve the quality of white LED and develop plant growth lighting, considerable efforts have been devoted to investigating red phosphor. Eu 3+ -activated phosphors are well-known red-emitting components due to their 5 D 0 - 7 F 1,2 transitions in various applications. It is also found that its 5 D 0 - 7 F 4 transition in the range of far-red wavelengths has potential applications in the fields of daily and agricultural lighting. In this study, two kinds of Eu 3+ -doped layered perovskite La 2 Ti 2 O 7 and A 2 La 2 Ti 3 O 10 (A = Li, Na, K) phosphors were synthesized by the solid-state method. The crystal structure, absorption, excitation, and emission spectra of all the samples were investigated in detail. Dissimilar luminescent behaviors of the studied samples were observed. Due to the different crystal structure and chemical composition of the host matrix, each compound exhibits a different emission spectrum. Specifically, Eu 3+ occupies a lower symmetric La 3+ site in A 2 La 2 Ti 3 O 10 (A = Li, Na, K) phosphors, resulting in an intense 5 D 0 - 7 F 4 far-red emission, while in La 2 Ti 2 O 7 :Eu 3+ , Eu 3+ gives a weak 5 D 0 - 7 F 4 emission. To the best of our knowledge, this is the first report that Eu 3+ exhibits a strong 5 D 0 - 7 F 4 far-red emission in the titanate host lattices with perovskite structure. Besides, A 2 La 2 Ti 3 O 10 :Eu 3+ (A = Li, Na, K) phosphors achieve higher photoluminescence efficiency than La 2 Ti 2 O 7 :Eu 3+ . Among them, the internal quantum efficiency of the optimized Li 2 La 2 Ti 3 O 10 :1.2Eu 3+ is about 84.7 %, and it has a better thermal stability (80 % at 125 °C). Furthermore, good photoelectric performances of red/white-LEDs fabricated by utilizing the representative Li 2 La 2 Ti 3 O 10 :1.2Eu 3+ as red/far-red components indicate that it has potential applications in indoor/outdoor lighting and plant growth lighting. This study provides a feasible way for developing efficient Eu 3+ -activated far-red optical materials.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2021
·
IF 2.694
Yuanyuan Han,Houchun Yan,Mai Han,Wei Wang,Jia Han,Tao Xing,Bing Li,Qingsong Li
The basic liquid–liquid equilibrium data of two systems {water + 2-propanol (IPA) + 1-octanol/n-propyl acetate} were measured. The distribution coefficients of the 2-propanol and the separation factors of the systems were calculated to analyze the extraction ability of the two extractants that extract IPA from water. The correlation model Hand equation was used to fit the data. The value of the linear correlation coefficient R2 > 0.99 indicates that the linear fit of the experimental data is good. The theoretical models NRTL and UNIQUAC were used to correlate the measured data. The deviation between experimental data and simulated data was calculated by the root mean square deviation (RMSD). The RMSD < 0.01 means that the two models were suitable for the regression of the systems studied in this work. GUI-MATLAB has validated the binary interaction parameters. The basic data obtained from this work can support the separation of water and IPA.
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2020
·
IF 2.888
Masumeh Mokhtarpour,Hemayat Shekaari
Thermodynamic properties of novel bio-based deep eutectic solvents (DESs) and their mixture with other solvents is of great importance in extraction and pharmaceutical sciences. In the present study new class of these neoteric sustainable solvents composed of amino acids and lactic acid have been prepared, density and speed of sound data for neat lactic acid/alanine, lactic acid/glycine and lactic acid/histidine and their aqueous mixture have been measured over the entire composition range at T = (298.15, 303.15, 308.15 and 313.15) K. Based on these data, some of the thermodynamic properties including the excess molar volumes ( V E ), apparent molar volume ( V ϕ ), excess isobaric thermal expansion ( α p , m E ), the excess molar isentropic compressibility ( κ E s,m ) and limiting apparent molar expansibility ( ϕ E , 1 0 ) have been calculated. For all of the studied systems above, these important properties have been analysed based on various solute-solvent interactions, occurring between the components of the mixtures. Furthermore, it has been found that all the investigated DESs act as a structure-breaker in water over the whole temperature range using Hepler’s constant. The properties have been correlated by the Redlich-Kister type equations.
✓ 已验证
DOI
高影响因子
Surfaces
·
2026
·Vol. 9
·期 2
·35
·
IF 2.7
Zhaoqing Xia,Yukai He,Lin Lv,Huan Niu,Zebin Zheng,Xiaoshan Liu,Wenjing Dong,Xunying Wang,Houzhao Wan,Guokun Ma,Hao Wang
Charge-trapping memory (CTM) exhibits significant potential in high-density memory, yet reliability degradation resulting from the coupling of program/erase (P/E) cycles and electrical stress remains a key bottleneck for large-scale commercialization. This study focuses on a Au/Al2O3/TiO2/p-Si CTM device, systematically investigating the device failure mechanism under continuously operating P/E cycles and constant voltage stress (CVS), with emphasis on elucidating the synergistic effect of bulk and interface defects on performance decay. Mechanistically, oxygen vacancies in TiO2serve as defect precursors, which form Frenkel pairs under electric field stress and further promote the formation of new defect precursors, thereby driving a self-sustaining defect evolution process. Interface traps, by contrast, arise from the cleavage of interfacial Si-H bonds triggered by electric field stress, resulting in a net elevation of the interface state density. The passive effects from the bulk and interface defects may give rise to issues, such as threshold voltage drift and decreased P/E speed. This work provides in-depth insights into the device failure mechanism of CTM, offering critical theoretical support for optimizing fabrication processes and enhancing long-term reliability.
✓ 已验证
DOI
高影响因子
Chemical Engineering Journal Advances
·
2022
·
IF 0
Hongqiang Cui,Yongze Cao,Lei Li,Guojian Li,Yuhang Zhang,Sai Xu,Yichao Wang,Xiangping Li,Baojiu Chen
A serious of Er 3+ /Yb 3+ co-doped Cs 2 Bi 2 Sr(P 2 O 7 )(PO 4 ) 2 (CBSPO) phosphors are prepared by solid phase reaction method, and the related thermal enhancement of up-conversion luminescence (UCL) are studied in depth under 980 and 1550 nm laser excitations. When doping concentration of Er 3+ is fixed at 0.1, and doping concentration of Yb 3+ is adjusted to improve the thermal enhancement effect in the temperature range from 303 to 723 K. The optimal doping concentrations of Er 3+ /Yb 3+ are found as 0.1 and 0.5, and the maximum enhancement of green UCL emission reaches 5.25 and 16.74 times under 980 and 1550 nm laser excitations, respectively. This is because of the combined action of electronic thermal agitation, phonon assisted transition and lattice distortion of doping Er 3+ sites. The change of structure with temperature is studied by variable temperature XRD. Additionally, based on FIR technique, the absolute sensitivity of 0.00955 K −1 at 557 K, 0.00643 K −1 at 509 K are got in CBSPO:0.1Er 3+ /0.3Yb 3+ under 980 nm laser excitation and in CBSPO:0.1Er 3+ /0.4Yb 3+ under 1550 nm laser excitation, respectively. The structure changes of polyphosphate with temperature provide new ideas for development of thermally enhanced up-conversion phosphors, which can be applied as optical thermometer at high temperature environment.
✓ 已验证
DOI
ACS Catalysis
·
2019
·
IF 12.221
Wenhui Li,Guanghui Zhang,Xiao Jiang,Yi Liu,Jie Zhu,Fanshu Ding,Zhongmin Liu,Xinwen Guo,Chunshan Song
Cobalt catalysts supported on TiO2 with different crystal forms (anatase and rutile) differ sharply in CO2 conversion and product selectivity for CO2 hydrogenation. The Co/rutile-TiO2 catalyst selectively catalyzed CO2 hydrogenation to CH4, while CO is the main product on the Co/anatase-TiO2 catalyst. In situ DRIFT (diffuse reflectance infrared Fourier transform) results have partially revealed the reaction pathway of CO2 hydrogenation on these two catalysts. On Co/rutile-TiO2, the reaction proceeds through the key intermediate formate species, which is further converted to CH4. Differently, the reaction on Co/anatase-TiO2 undergoes CO2 → *CO, which desorbs to form gas-phase CO instead of subsequent hydrogenation. The strongly bonded *CO is required to enhance the subsequent hydrogenation. By simply changing the calcination temperature of anatase TiO2, the product selectivity can be tuned from CO to CH4 with a significant increase in CO2 conversion due to the surface phase transition of the anatase to the rutile phase. The addition of Zr, K, and Cs further improves the CO, CO2, and H2 adsorption in both the capacity and strength over anatase- and rutile-supported catalysts. The Zr modification makes the reaction pathway over anatase-supported catalyst proceed via the intermediate formate species and enables the subsequent hydrogenation to CH4. In addition, the surface C/H ratio increases significantly in the presence of promoters (unpromoted < Zr-promoted < K-Zr-promoted ∼ Cs-Zr-promoted), which leads to the highest C2+ selectivity of 17% with 70% CO2 conversion over K-Zr-Co/anatase-TiO2 catalyst. These results reveal mechanistic insights into how the product distribution of Co/TiO2 catalysts can be manipulated through adjusting the adsorption performance and surface C/H ratio.
研究领域:
催化化学
·
材料化学
·
多相催化
·
CO2利用
·
表面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2012
·
IF 1.693
Ru-Hao He,Bing-Wen Long,Ying-Zhou Lu,Hong Meng,Chun-Xi Li
To study the possibility of using ionic liquids (ILs) as a novel solvent for the absorption of hydrogen chloride (HCl) from the industrial tail gases, the solubility of HCl gas in three ILs has been measured at four temperatures, (298.15, 323.15, 348.15, and 363.15) K, in the pressure range of (0 to 100) kPa. The ILs used are 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), 1-hexyl-3-methylimidazolium chloride ([Hmim]Cl), and 1-octyl-3-methylimidazolium chloride ([Omim]Cl). The results indicate that these ILs show high solubility for HCl gas, and the solubility decreases with the increasing length of the alkyl substitutes of the ILs, following the order [Bmim]Cl > [Hmim]Cl > [Omim]Cl. The solubility of HCl in [Bmim]Cl at 298.15 K is about 0.68 mole fraction at ca. 100 kPa partial pressure of HCl, which is much higher than that of 36.5 % HCl aqueous solution. The solubility of different ILs is discussed in detail, and the experimental data (P–T–x) are correlated successfully by an empirical relation.
研究领域:
化学工程
·
绿色化学
·
气体分离
·
离子液体
·
环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2022
·
IF 3.269
Zhan-Ping Qiao,Xin Chen,Qi-Chao Yang
Using an isothermal equilibrium method, the phase equilibrium of the ternary systems CsCl–CdCl 2 –H 2 O and CsBr–CdBr 2 –H 2 O were studied at T = 298.1 K. In the phase diagram of the system CsCl–CdCl 2 –H 2 O, the solid phases of CsCdCl 3 and Cs 2 CdCl 4 , besides CsCl and CdCl 2 ·2.5H 2 O, were discovered. The phase diagram of the system CsBr–CdBr 2 –H 2 O contains five crystallization fields for the solid phases CdBr 2 ·4H 2 O, CsCdBr 3 , Cs 5 Cd 2 Br 9 , Cs 3 CdBr 5 and CsBr. The new solid phases of CsCdCl 3 and CsCdBr 3 are congruently soluble, and Cs 2 CdCl 4 , Cs 5 Cd 2 Br 9 and Cs 3 CdBr 5 are incongruently soluble in the aqueous system. The experimental solubility data and phase diagram s for the ternary systems show more practical application for the obtained cadmium-based halide perovskite. The five new solid phase have been analyzed by X-ray diffraction and thermogravimetry/derivative thermogravimetry. By measuring the standard molar enthalpies of solution of the compounds, the standard molar enthalpies of formation of CsCdCl 3 , Cs 2 CdCl 4 , CsCdBr 3 , Cs 5 Cd 2 Br 9 , Cs 3 CdBr 5 were determined to be –(873.3 ± 0.7) kJ·mol −1 , –(1325.6 ± 0.9) kJ·mol −1 , –(742.8 ± 0.7) kJ·mol −1 , –(2710.0 ± 1.3) kJ·mol −1 and –(1558.1 ± 1.0) kJ·mol −1 , respectively.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2022
·
IF 3.119
Yun-Jia Liu,Liu-Ying Yu,Ke-Jun Wu,Chao-Hong He
In this work, the thermal conductivities of 1,3-dichloro-2-propanol + N,N-dimethylformamide (DMF) were measured from 303 to 368 K at pressures up to 15.10 MPa by using a transient hot-wire method. Measurements were made for six compositions over the entire concentration range from 0 to 1 mass fractions of DMF, namely, 0.000, 0.200, 0.400, 0.600, 0.800, and 1.000 mass fractions of DMF. The experimental data were correlated as a function of temperature, pressure, and mass fraction of DMF. The expanded uncertainty of the obtained data was estimated to be 2% with a confidence level of 0.95 (k = 2).
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2023
·
IF 2.6
Chun-Tao Hu,Yun-Yun Gao,Shi-Hua Sang,Yu-Qiu Cen,Xiao-Feng Guo,Cheng Li
To efficiently exploit and utilize bromine-rich brine resources of China, solid–liquid phase equilibria of the quinary system NaBr–KBr–MgBr2–SrBr2–H2O (saturated with KBr) and the quaternary system NaBr–MgBr2–SrBr2–H2O at 308.2 K were studied in detail by the isothermal dissolution equilibrium method. The dry salt phase diagram of the quinary system NaBr–KBr–MgBr2–SrBr2–H2O (saturated with KBr) includes one invariant point, three isothermal dissolution curves, and three crystallization regions (NaBr·2H2O, KBr·MgBr2·6H2O, and SrBr2·6H2O) under the condition of KBr saturation. And the crystallization region of KBr·MgBr2·6H2O is the smallest, so KBr·MgBr2·6H2O is difficult to crystallize and precipitate. Similarly, The dry salt phase diagram of the quaternary system NaBr–MgBr2–SrBr2–H2O is composed of two invariant points, five isothermal solubility curves, and four crystallization fields, which are hydrate salts NaBr·2H2O, MgBr2·6H2O, and SrBr2·6H2O and anhydrous simple salt NaBr. The crystallization region of MgBr2·6H2O is the smallest, the solubility of magnesium bromide is the largest, and it is difficult to crystallize and precipitate in this saturated solution. Furthermore, the mixing ion-interaction parameter ΨNa, Sr, Br of Pitzer’s model is fitted, which can be used for the subsequent prediction of phase equilibria containing strontium system. In addition, the solubilities of salts in the quinary system and the quaternary subsystem were theoretically predicted, and the experimental value was compared with the calculated value. The calculated value was in good agreement with the experimental value.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2023
·
IF 2.6
Han Yue,Yuxiang Liu,Yidong Gu,Xiwei Hu,Jiaming Zhu,Qunsheng Li
The solubility of trans-3-hydroxycinnamic acid in pure solvents (methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, methyl acetate, ethyl acetate, and n-propyl acetate) and (ethanol + ethyl acetate) cosolvent mixtures was measured by the gravimetric method from 293.15 to 333.15 K in normal pressure. The experimental results show that the solubility of 3-HCA(E) in alcohol solvents is greater than in ester solvents, which conforms to “like dissolves like”. On this basis, the experimental result was correlated with semiempirical models (the modified Apelblat, van’t Hoff, λh, Jouyban–Acree–van’t Hoff equation, and combined model) and activity coefficient models (Wilson, NRTL, and UNIQUAC equation). The modified Apelblat model has the best correlation of the experimental data, with an ARD of less than 0.5% for pure solvents and cosolvent mixtures. The solvent effect was calculated by the KAT-LSER equation, showing that the hydrogen bond alkalinity of solvents–solutes (β) and the solvent self-association (δH) significantly influence the solubility of 3-HCA(E), accounting for 32.46 and 55.02%, respectively. Finally, the thermodynamic parameters (ΔHmix, ΔSmix, ΔGmix,%ξH, and %ξTS) were calculated. Negative values of both ΔHmix and ΔGmix indicate that the mixing process of 3-HCA(E) is exothermic and spontaneous. The Gibbs energy of the mixing process is jointly contributed by enthalpy and entropy.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Yu Dong,Xin Yin,Yapeng Cao,Shufeng Shen
Water-lean absorbent has great potential in energy savings over aqueous amines for CO 2 capture. Measurements on density and viscosity for the ternary systems of monoethanolamine (MEA), 2-(methylamino)ethanol (MAE), 2-(ethylamino)ethanol (EAE) or 2-(butylamino)ethanol (BAE) + 2-butoxyethanol (EGBE) + water have been performed at atmospheric pressure and temperatures from 293.15 to 353.15 K. The total amine concentrations in these systems were held at two constant mass fractions in the range of 30-60 mass%. Excess molar volume ( V E ) and viscosity deviation (Δ η ) of the ternary systems were also derived from the experimental data and correlated with Cibulka parameters with the aid of Redlich-Kister equation to fit the measured ternary properties from their pure components. The addition of water into the binary (amine +EGBE) systems can affect greatly the molecular interactions . The V E values of the ternary blends are found to be negative over the investigated conditions. However, Δ η values are observed to be positive except in the rich (amine + EGBE) concentration region. The variations of V E and Δ η were represented and interpreted with molecular interactions and structural effects.
✓ 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）