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Chinese Journal of Polymer science 2017年第4期35卷 558-568页

作者： Rong Liang Yi-chun Chen Chun-qiu Zhang Jing Yin Xue-lei Liu Lu-kai Wang Rui Kong Xin Feng 杨进军 school of Environmental science and Safety engineering Tianjin University of Technology Tianjin 300384 China school of Mechanical engineering Tianjin University of Technology Tianjin 300384 China

Zinc phenylphosphonate （PPZn）, a benign and biocompatible nucleating agent, was prepared and incorporated into the biodegradable poly（ethylene adipate）（PEA） to investigate its effect on the crystallization behavior, crystallization kinetics and spherulite morphology of PEA. Upon addition of PPZn, the crystallization temperature and crystallinity of PEA in the non-isothermal crystallization process increased significantly. Analysis of crystallization kinetics by Avrami equation suggests that the crystallization time shortened greatly and crystallization rate increased markedly after addition of PPZn. In the presence of PPZn, the spherulite size decreased and spherulite density increased significantly. It suggests that PPZn is an efficient nucleating agent for the crystallization of PEA. The accelerated crystallization in the presence of PPZn is mainly attributed to the epitaxial nucleation of PEA crystals on the surface of PPZn crystals, that is, a perfect lattice matching between PEA crystal and PPZn crystal occurs.

关键词： Crystallization kinetics Epitaxial growth Poly(ethylene adipate) Nucleating agent

High sensitivity SPR refractive index sensor with high resolution based on anti-resonance fiber

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Optoelectronics Letters 2022年第4期18卷 204-209页

作者： ZHANG Ailing LI Yueting PAN Fei PAN Honggang LIU Fei engineering Research Center of Optoelectronic Devices&Communication technology Ministry of EducationTianjin Key Laboratory of Film Electronic and Communication DevicesSchool of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China

We proposed a surface plasmon resonance(SPR)refractive index sensor based on hollow-core anti-resonance fiber(HC-ARF).Gold was filled in two symmetric cladding tubes of the fiber,while the analyte was filled in central air *** sensing performance was investigated by the finite element method(FEM).Results show that two resonance peaks(a crossing point around 1030 nm and an anti-crossing region around 1065 nm)appear for x-polarization(x-pol)core mode coupling with the surface plasmon polariton(SPP)***,the sensitivity was also *** sensitivity increased with the increase of cladding tube thickness *** sensor with thickness t=1.7μm gave a wavelength sensitivity of 7350—14790 nm/RIU in the refractive index range of 1.33—1.45 with resonance wavelength from 1900 nm to 450 ***,the resolution of 10^(-6) RIU was *** to high sensitivity and resolution,the proposed sensor has potential applications in glucose detection.

关键词： fiber polarization refractive

Enhanced photoluminescence of CaTiO_3:Eu^(3+) red phosphors prepared by H_3BO_3 assisted solid state synthesis

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Journal of Rare Earths 2013年第6期31卷 555-558页

作者：刘盼盼尹静米晓杨张乐喜别利剑 school of Materials science and engineering Tianjin University of Technology school of Environmental science and Safety engineering Tianjin University of Technology tianjin Key Lab for Photoelectric Materials & Devices Tianjin University of Technology

CaTiO3：Eu3＋ red phosphors were prepared using H3BO3 assisted solid state synthesis. The structure and morphology of the obtained sample were observed by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. And the luminescence property was measured using photoluminescence excitation （PLE） and photoluminescence （PL） spectra, respectively. In the excitation spectra, main excitation peaks of the prepared samples were centered at 397 and 465 nm, revealing that these phosphors could be excited by commercial GaN- and InGaN-typed light emitting diodes （LEDs）. Dominant emission peaks of the phosphors were located at 616 nm, owing to the transition of 5D0→7F2 of Eu3＋. In the optimum condition, CaTiO3：3%Eu3＋ phosphor was obtained at a sintering temperature of 1200 °C in air with a content of 20 mol.% H3BO3 addition. When excited by 397 nm irradiation, the PL intensity of as-prepared red phosphor was 2.2 times higher than that of samples obtained by traditional solid state synthesis, while the PL intensity was 3 times higher than that excited by 465 nm irradiation. The added H3BO3 improved the crystallinity, and increased the color purity, implying the potential to be a promising red phosphor in white light emitting diodes （WLEDs）.

关键词： red phosphor calcium titanate WLED photoluminescence rare earths

Simulation and optimization of dopant-free asymmetric heterojunction solar cells

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Optoelectronics Letters 2023年第6期19卷 337-346页

作者： ZHENG Qiaoqiao YUAN Yujie HOU Guofu LI Wei TAO Ke PENG Zhuo tianjin Key Laboratory of Film Electronic and Communication Devices School of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China Institute of Photoelectronic Thin Film Devices and technology Nankai UniversityTianjin 300350China

In order to further study doping-free asymmetric heterojunction(DASH) solar cells,we used AFORS-HET software to optimize the structure of Al/SnO_(2)/a-Si:H(i)/c-Si(p)/a-Si:H(i)/NiO_(x)/*** a certain adjustment range,a series of simulations were carried out on the band gap,electron affinity,thickness and work function(WF) of NiO_(x),thickness and WF of SnO_(2),and the thickness of a-Si:H(i).After the above optimization,21.08% efficiency was obtained at 300 *** study shows that the solar cells with this structure have good light absorption properties in a very wide *** present simulation provides instructive suggestions for follow-up experiments of DASH solar cells.

关键词： spectrum asymmetric optimization

Heterogeneous activation of persulfate by CuMgAl layered double oxide for catalytic degradation of sulfameter

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Green Energy & Environment 2022年第1期7卷 105-115页

作者： Hongmin Zhang Qingzhu Jia Fangyou Yan Qiang Wang school of Marine and Environmental science Tianjin Marine Environmental Protection and Restoration Technology Engineering CenterTianjin University of Science and TechnologyTianjin300457China school of Chemical engineering and Material science Tianjin University of Science and TechnologyTianjin300457China

In this study,a series of CuMgAl layered double oxides(CuMgAl-LDOs)were obtained via calcination of CuMgAl layered double hydroxides(CuMgAl-LDHs)synthesised via a co-precipitation *** results show that CuMgAl-LDO can be prepared using an optimal Cu:Mg:Al molar ratio of 3:3:2,NaOH:Na_(2)CO_(3)molar ratio of 2:1,and calcination temperature of 600°***-LDO is a characteristic of mesoporous material with a lamellar structure and large specific surface *** removal efficiency of sulfameter(SMD)based on CuMgAl-LDO/persulfate(PS)can reach>98%over a wide range of initial SMD concentrations(5–20 mg L^(-1)).The best removal efficiency of99.49%was achieved within 120 min using 10 mg L^(-1)SMD,0.3 g L^(-1)CuMgAl-LDO,and 0.7 mmol L^(-1)*** analysis showed that the degradation of SMD was in accordance with a quasi-first-order kinetic *** stability of the CuMgAl-LDO catalyst was verified by the high SMD removal efficiency(>97%within 120 min)observed after five recycling tests and low copper ion leaching concentration(0.89 mg L^(-1)),which is below drinking water quality standard of 1.3 mg L^(-1)permittable in the *** scavenging experiments suggest that SO_(4)^(-)is the primary active species participating in the CuMgAl-LDO/PS ***,our mechanistic investigations based on the radical scavenging tests and X-ray photoelectron spectroscopy(XPS)results indicate that Cu^((II))-Cu^((III))-Cu^((II))circulation is responsible for activating PS in the degradation of SMD and the degradation pathway for SMD was ***,the results presented in this work demonstrate that CuMgAl-LDO may be an efficient and stable catalyst for the activation of PS during the degradation of organic pollutants.

关键词： CuMgAl-LDO Heterogeneous catalysis Activated persulfate Sulfameter Reaction mechanism

Microstructure Evolution of Primary γ′ Phase in Ni3Al-Based Superalloy

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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1709-1726页

作者： Xin He Jianbo Zhang Yuanyi Peng Jingan Li Jian Ding Chang Liu Xingchuan Xia Xueguang Chen Yongchang Liu school of Material science and engineering Hebei University of TechnologyTianjin 300130China school of Material science and engineering Tianjin UniversityTianjin 300130China

In this work,water cooling,air cooling(AC)and furnace cooling(FC)were applied to investigate the effect of cooling rate on microstructure evolution of primaryγ′in a newly designed Ni3Al-based *** results showed that nucleation rate of primaryγ′increased with increasing cooling *** addition,higher cooling rate shortened growth period of primaryγ′,which made its morphology close to the initial precipitatedγ′.For AC and FC specimens,due to the lower cooling rate,primaryγ′possessed longer growth period and its morphology was mainly due to the evolution of lattice misfit betweenγand primaryγ′.Meanwhile,growth of primaryγ′depended on lattice misfit distribution between its corner and edge ***,primaryγ′morphologies of sphere,cube and concave cube with tip corners were illustrated by considering interaction between elemental diffusion and elastic strain energy.

关键词： Ni3Al-based alloy Primaryγ′ Cooling rate Nucleation rate Lattice misfit

Three-Dimensional N-Doped Carbon Nanotube/Graphene Composite Aerogel Anode to Develop High-Power Microbial Fuel Cell

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Energy & Environmental Materials 2023年第3期6卷 161-169页

作者： Shixuan Jin Yiyu Feng Jichao Jia Fulai Zhao Zijie Wu Peng Long Feng Li Huitao Yu Chi Yang Qijing Liu Baocai Zhang Hao Song Wei Feng school of Material science and engineering Tianjin UniversityTianjin 300350China school of Chemical engineering and technology Tianjin UniversityTianjin 300350China

Optimizing the structure of electrode materials is one of the most effective strategies for designing high-power microbial fuel cells(MFCs).However,electrode materials currently suffer from a series of shortcomings that limit the output of MFCs,such as high intrinsic resistance,poor electrolyte wettability,and low microbial load ***,a three-dimensional(3D)nitrogen-doped multiwalled carbon nanotube/graphene(N-MWCNT/GA)composite aerogel is synthesized as the anode for *** nitrogen-doped GA,MWCNT/GA,and N-MWCNT/GA,the macroporous hydrophilic N-MWCNT/GA electrode with an average pore size of 4.24μm enables high-density loading of the microbes and facilitates extracellular electron transfer with low intrinsic ***,the hydrophilic surface of N-MWCNT can generate high charge mobility,enabling a high-power output performance of the *** consequence,the MFC system based on N-MWCNT/GA anode exhibits a peak power density and output voltage of 2977.8 mW m^(−2)and 0.654 V,which are 1.83 times and 16.3%higher than those obtained with MWCNT/GA,*** results demonstrate that 3D N-MWCNT/GA anodes can be developed for high-power MFCs in different environments by optimizing their chemical and microstructures.

关键词： anode graphene aerogel microbial fuel cell N-doped carbon nanotube

Design of a transversal equalizer for electronic dispersion compensation in optical communication links

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Optoelectronics Letters 2011年第1期7卷 37-40页

作者：高振斌石勇王博曾祥烨 Information engineering Department Hebei University of Technology tianjin integrated circuit Design Center

A programmable transversal equalizer for electronic dispersion compensation(EDC) in optical fiber communication systems is *** on the SiGe technology with a cut-off frequency of 80 GHz,the equalizer consists of 6 seriesparallel amplifiers as delay units and 7 Gilbert variable gain amplifiers as taps,which ensure that the equalizer can work at the bit rate of 10 Gb/*** different tap gains,the forward voltage gain of the transversal equalizer varies,which demonstrates that the equalizer has various filtering characteristics such as low pass filtering,band pass filtering,band reject filtering,and notch filtering,so it can effectively simulate the inverse transfer function of dispersive channels in optical communications,and can be used for compensating the inter-symbol interference and other nonlinear problems caused by *** equalizer(including pads) occupies an area of 0.40 mm × 1.08 mm,and its total power dissipation is 400 mW with 3.3 V power supply.

关键词： Communication systems Dispersion compensation Electromagnetic dispersion Inverse problems Optical fibers Voltage regulators

Study on release rate of latent heat in Czochralski silicon growth

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Rare Metals 2006年第z2期25卷 51-54页

作者： REN Bingyan YANG Jiankun LI Yanlin LIU Xiaoping WANG Minhua school of Material science and engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China

The pulling rate in czochralski silicon (CZSi) growth is important for reducing the cost of solar cell. In this paper, double-heater, heat shield and composite argon duct system were introduced in the Ф450 mm hot zone of a Czochralski furnace. The pulling rate under different thermal system was recorded in experiments. Argon flow and temperature fields were simulated by finite element method(FEM). Experimental results and numerical simulation indicate that double-heater and composite argon duct system can enhance obviously the release rate of latent heat. In Φ 200 mm Czochralski silicon (CZSi) growth, average pulling rate can increase from 0.6 mm·min-1 in the conventional hot zone to 0.8 mm·min-1 in the modified hot zone.

关键词： CZSi latent heat double-heater heat shield numerical simulation

Sintering process and grain growth of Mn-Zn ferrite nanoparticles

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Rare Metals 2006年第z1期25卷 526-530页

作者： WANG Xin CUI Yinfang WANG Yongming HAO Shunli LIU Chunjing school of Material science and engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China

The density, microstructure and magnetic properties of non-doped Mn-Zn ferrite nanoparticles sintered compacts were investigated. The compacts of non-doped Mn-Zn ferrite nanoparticles were sintered by segmented-sintering process at lower sintering temperature. The density of sintered samples was measured by Archimedes method, and the phase composition and microstructure were examined by XRD and SEM. The sintered Mn-Zn ferrite magnetic measurements were carried out with Vibrating Sample. The results show that the density of sintered compacts increases with the rising of sintering temperature, achieving 4.8245 g·cm-3 when sintered at 900 ℃, which is the optimal density of Mn-Zn functional ferrite needed and from the fractured surface of sintered samples, it can be seen that the grain grows well with small grain size and homogeneous distribution.

关键词： Mn-Zn ferrite sintering temperature grain growth density magnetic properties