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Synthesis and luminescent properties of BaGd_2O_4:Eu^(3+) phosphors with highly efficient red-emitting

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Journal of Rare Earths 2018年第8期36卷 795-801页

作者： yue Li Jinkai Li Zongming Liu Weilin zhao School of Materials Science and Engineering University of Jinan

The BaGd（2-2 x）Eu（2 x）O4（BG, x = 0.01-0.09） phosphors were successfully synthesized via the sol-gel method,and BaY（2-2 y）Eu（2 y）O4（BY, y = 0.005-0.07） phosphors were included for comparison. The pure phase BG phosphors with the ordered CaFe2 O4-type structure are obtained by annealing at 1300℃ for5 h. The phosphors with uniform particle size of 120 nm and good dispersion display typical Eu^3＋emission with the strongest peak at 613 nm（^5 D0→^7 F2 transition of Eu3＋） under optimal excitation band at 262 nm（CTB band）. The presence of Gd^3＋ excitation bands on the PLE spectra monitoring the Eu3＋emission directly proves an evidence of Gd^3＋-Eu^3＋ energy transfer. Owing to the concentration quenching, the optimum content of Eu3＋ addition is 5 at%（x = 0.05）, and the quenching mechanism is determined to be the exchange reaction between Eu3＋. All the BG samples have similar color coordinates and temperature of（0.64 ± 0.02, 0.36 ± 0.01） and 2000 ± 100 K,respectively. The lifetime value of BaGd（1.9）Eu（0.1）O4 for 613 nm is fitted to be 2.19 ± 0.01 ms, and the Eu^3＋ concentration does not change the lifetime significantly. Owing to the Gd^3＋-Eu^3＋ energy transfer, the luminescent intensity of the BaGd（1.9）Eu（0.1）O4 phosphor is better than BY system. The BG system served as a new type of phosphor is expected to be widely used in lighting and display areas.

关键词： BaGd2O4 host Eu^3+ doped Sol-gel method Luminescent properties Rare earths

Preparation and evaluation of α-Al2O3 supported lithium ion sieve membranes for Li^+ extraction

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2312-2318页

作者： Feng Xue Xiaoxian Zhang yue Niu Chenhao Yi Shengui ju Weihong Xing College of Chemical Engineering Nanjing Tech UniversityNanjing 211816China

Spinel lithium manganese oxide ion-sieves have been considered the most promising adsorbents to extract Li^+ from brines and sea ***,we report a lithium ion-sieve which was successfully loaded onto tubular α-Al2 O3 ceramic substrates by dipping crystallization and post-calcination *** lithium manganese oxide Li4 Mn5 O(12)was first synthesized onto tubular α-Al2 O3 ceramic substrates as the ion-sieve precursor(i.e.L-AA),and the corresponding lithium ion-sieve(i.e.H-AA) was obtained after acid *** chemical and morphological properties of the ion-sieve were confirmed by X-ray diffraction(XRD) and scanning electron microscopy(SEM).Both L-AA and H-AA showed characteristic peaks of α-Al2 O3 and cubic phase Li4 Mn5 O(12) and the peaks representing cubic phase could still exist after *** lithium manganese oxide Li4 Mn5 O(12) could be uniformly loaded not only on the surface of α-Al2 O3 ubstrates but also inside the ***,we found that the equilibrium adsorption capacity of H-AA was 22.9 mg·g^-*** 12 h adsorption,the adsorption balance was *** 5 cycles of adsorption,the adsorption capacity of H-AA was 60.88% of the initial adsorption *** process of H-AA adsorption for Li^+correlated with pseudo-second order kinetic model and Langmuir *** thermodynamic parameters regarding enthalpy(△N), Gibbs free energy(△G) and entropy(AS) were *** the dynamic adsorptiondesorption process of H-AA,the H-AA exhibited excellent adsorption performance to Li^+ with the Li^+ dynamic adsorption capacity of 9.74 mg·g^-1 and the Mn^2+dissolution loss rate of 0.99%.After 3 dynamic adsorption-desorption cycles,80% of the initial dynamic adsorption capacity was still kept.

关键词： Lithium α-Al2O3 tube Ion sieve Adsorption Li4Mn5O(12)

Removal of Pb(Ⅱ) from aqueous solutions using waste textiles/poly(acrylic acid) composite synthesized by radical polymerization technique

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Journal of Environmental Sciences 2018年第5期30卷 368-377页

作者： Tao Zhou Fafa Xia yue Deng Youcai zhao The State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University

Waste textiles（WTs） are the inevitable outcome of human activity and should be separated and recycled in view of sustainable development. In this work, WT was modified through grafting with acrylic acid（AA） via radical polymerization process using ceric ammonium nitrate（CAN） as an initiator and microwave and/or UV irradiation as energy supply. The acrylic acid-grafted waste textiles（WT-g-AA） thus obtained was then used as an adsorbent to remove Pb（Ⅱ） from Pb（Ⅱ）-containing wastewater. The effects of p H, initial concentrations of Pb（Ⅱ） and adsorbent dose were investigated, and around 95% Pb（Ⅱ） can be removed from the aqueous solution containing 10 mg/L at p H 6.0–8.0. The experimental adsorption isotherm data was fitted to the Langmuir model with maximum adsorption capacity of35.7 mg Pb/g WT-g-AA. The Pb-absorbed WT-g-AA was stripped using dilute nitric acid solution and the adsorption capacity of Pb-free material decreased from 95.4%（cycle 1） to91.1%（cycle 3）. It was considered that the WT-g-AA adsorption for Pb（Ⅱ） may be realized through the ion-exchange mechanism between ／COOH and Pb（Ⅱ）. The promising results manifested that WT-g-AA powder was an efficient, eco-friendly and reusable adsorbent for the removal of Pb（Ⅱ） from wastewater.

关键词： Adsorption Pb(Ⅱ) Waste textiles Graft copolymefization

Experimental Investigation of Vibration Response of A Free-Hanging Flexible Riser Induced by Internal Gas-Liquid Slug Flow

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China Ocean Engineering 2018年第6期32卷 633-645页

作者： ZHU Hong-jun zhao Hong-lei GAO yue State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University

The vibration response of a free-hanging flexible riser induced by internal gas-liquid slug flow was studied experimentally in a small-diameter tube model based on Froude number criterion. The flow regime in a curved riser model and the response displacements of the riser were simultaneously recorded by high speed cameras. The gas superficial velocity ranges from 0.1 m/s to 0.6 m/s while the liquid superficial velocity from 0.06 m/s to 0.3 m/*** slugging type 3, unstable oscillation flow and relatively stable slug flow were observed in the considered flow rates. Severe slugging type 3 characterized by premature gas penetration occurs at relatively low flow rates. Both the cycle time and slug length become shorter as the gas flow rate increases. The pressure at the riser base undergoes a longer period and larger amplitude of fluctuation as compared with the other two flow regimes. Additionally, severe slugging leads to the most vigorous in-plane vibration. However, the responses in the vertical and horizontal directions are not synchronized. The vertical vibration is dominated by the second mode while the horizontal vibration is dominated by the first mode. Similar to the vortex-induced vibration, three branches are identified as initial branch, build-up branch and descending branch for the response versus the mixture velocity of gas-liquid flow.

关键词： gas-liquid two-phase flow severe slugging liquid slug flexible riser flow-induced vibration

A 3D-printed microfluidic gradient concentration chip for rapid antibiotic-susceptibility testing

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Bio-Design and Manufacturing 2022年第1期5卷 210-219页

作者： Huilin Zhang Yuan Yao yue Hui Lu Zhang Nanjia Zhou Feng ju College of Environmental&Resource Sciences Zhejiang UniversityHangzhou 310058China Key Laboratory of Coastal Environment and Resources of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024China Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024China Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province Hangzhou 310024China

The rise of antibiotic resistance as one of the most serious global public health threats has necessitated the timely clinical diagnosis and precise treatment of deadly bacterial *** identify which types and doses of antibiotics remain effective for fighting against multi-drug-resistant pathogens,the development of rapid and accurate antibiotic-susceptibility testing(AST)is of primary *** methods for AST in well-plate formats with disk diffusion or broth dilution are both labor-intensive and operationally *** microfluidic chip provides a versatile tool for evaluating bacterial AST and resistant *** this paper,we develop an operationally simple,3D-printed microfluidic chip for AST which automatically deploys antibiotic concentration gradients and fluorescence intensity-based reporting to ideally reduce the report time for AST to within 5 *** harnessing a commercially available,digital light processing(DLP)3D printing method that offers a rapid,high-precision microfluidic chip-manufacturing capability,we design and realize the accurate generation of on-chip antibiotic concentration gradients based on flow resistance and diffusion *** further demonstrate the employment of the microfluidic chip for the AST of *** to representative clinical antibiotics of three classes:ampicillin,chloramphenicol,and *** determined minimum inhibitory concentration values are comparable to those reported by conventional well-plate *** proposed method demonstrates a promising approach for realizing robust,convenient,and automatable AST of clinical bacterial pathogens.

关键词： Microfluidics Gradient concentration chip Digital light processing Antibiotic-susceptibility test Bacteria

Low Light Level Image Enhancement Based on Multi-layer Slicing Photon Localization Algorithm

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Chinese Journal of Electronics 2018年第3期27卷 521-526页

作者： YING Changsheng zhao Peng yue Dan LI Ye School of Science Changchun University of Science and Technology School of Computer Science and Technology Jilin Normal University

Low light level(LLL) images, which were captured by Intensified CCD(ICCD) camera equipped with an image intensifier, suffer low spatial resolution and contrast due to noise and dispersion. By dividing the integration time into intervals short enough, we obtain photon images where photon formed spots were nearly nonoverlapping. In order to enhance LLL images, we propose a Multi-layer slicing(MLS) photon localization algorithm based on photon images. The photon image is sliced by different planes. Photon spatial distribution(PSD) information is acquired by using pro jected area ratio, circularity and the number of slices. The enhanced LLL image is obtained by accumulating time-domain correlated PSD images. Experimental results show that the visual effects,spatial frequencies and contrast of the enhanced image are significantly improved.

关键词： Noise Dispersion Spatial resolution Multi-layer slicing(MLS) Photon spatial distribution(PSD)

Determination of the Observation Area for Metallographic Microstructure of GH4033 Superalloy in a Uniaxially Thermo-Mechanical Compression Experiment

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Acta Metallurgica Sinica(English Letters) 2014年第3期27卷 494-500页

作者： Fengli Sui yue Zuo jun zhao Baoguo Ma School of Metallurgical Engineering Anhui University of Technology Special Steel Branch Baoshan Iron and Steel Co.Ltd

Based on two-dimensional （2D） rigid-plastic finite element （FE） method, the optimum observation area for metallographic microstructure and the influence of the height-diameter ratio on which were analyzed for the cylindrical samples with the diameter of 8 mm and different heights from 8 to 16 mm in nonuniform compressive experiments. It is shown that the representative metallographic observation area relevant to the applied deformation condition is located at about 0.835 of the radius from the center of the sample to the solder joint between the sample and the thermocouples. At the same time, the microstructure in that area is more appropriate as the height of the sample is 12 mm. The related parameters of GH4033 superalloy were adopted in the FE analysis, and the validity of this analysis was verified by the compressive experiments.

关键词： GH4033 superaUoy Uniaxial compression Uniformity Height-diameter ratio Metallographic observation area Finite element

Dynamic programming methodology for multi-criteria group decision-making under ordinal preferences

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Journal of Systems Engineering and Electronics 2010年第6期21卷 975-980页

作者： Wu Li Guanqi Guo Chaoyuan yue Yong zhao School of Information and Communication Engineering Hunan Institute of Science and Technology Yueyang 414006 E R. China Institute of Systems Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China

A method of minimizing rankings inconsistency is proposed for a decision-making problem with rankings of alternatives given by multiple decision makers according to multiple criteria. For each criteria, at first, the total inconsistency between the rankings of all alternatives for the group and the ones for every decision maker is defined after the decision maker weights in respect to the criteria are considered. Similarly, the total inconsistency between their final rankings for the group and the ones under every criteria is determined after the criteria weights are taken into account. Then two nonlinear integer programming models minimizing respectively the two total inconsistencies above are developed and then transformed to two dynamic programming models to obtain separately the rankings of all alternatives for the group with respect to each criteria and their final rankings. A supplier selection case illustrated the proposed method, and some discussions on the results verified its effectiveness. This work develops a new measurement of ordinal preferences’ inconsistency in multi-criteria group decision-making （MCGDM） and extends the cook-seiford social selection function to MCGDM considering weights of criteria and decision makers and can obtain unique ranking result.

关键词： multi-criteria group decision-making (MCGDM) ordinal preference minimum deviation method dynamic programming Cook-Seiford social selection function.

Effects of Rattling Behavior of K and Cd Atoms along Different Directions in Anisotropic KCdAs on Lattice Thermal Transport and Thermoelectric Properties

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Energy & Environmental Materials 2024年第6期7卷 388-398页

作者： yue Wang Yinchang zhao jun Ni Zhenhong Dai Department of Physics Yantai UniversityYantai 264005China State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China

We employ advanced first principles methodology,merging self-consistent phonon theory and the Boltzmann transport equation,to comprehensively explore the thermal transport and thermoelectric properties of ***,the study accounts for the impact of quartic anharmonicity on phonon group velocities in the pursuit of lattice thermal conductivity and investigates 3ph and 4ph scattering processes on phonon *** various methodologies,including examining atomic vibrational modes and analyzing 3ph and 4ph scattering processes,the article unveils microphysical mechanisms contributing to the lowκL within *** features include significant anisotropy in Cd atoms,pronounced anharmonicity in K atoms,and relative vibrations in non-equivalent As atomic *** atoms,situated between As layers,exhibit rattling modes and strong lattice anharmonicity,contributing to the observed lowκ*** flat bands near the valence band maximum translate into high PF,aligning with ultralowκL for exceptional thermoelectric *** optimal temperature and carrier concentration doping,outstanding ZT values are achieved:4.25(a(b)-axis,p-type,3×10^(19)cm^(−3),500 K),0.90(c-axis,p-type,5×10^(20)cm^(−3),700 K),1.61(a(b)-axis,n-type,2×10^(18)cm^(−3),700 K),and 3.06(c-axis,n-type,9×10^(17)cm^(−3),700 K).

关键词： anharmonic lattice dynamics electron transport characteristics first principles calculation lattice thermal transport octahedron thermoelectric properties