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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 60-70页

作者： Hai Li Aibing Jin Shuaijun Chen Yiqing Zhao you ju Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mine University of Science and Technology BeijingBeijing 100083China School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China

The challenge of high temperatures in deep mining remains harmful to the health of workers and their production efficiency The addition of phase change materials (PCMs) to filling slurry and the use of the cold storage function of these materials to reduce downhole temperatures is an effective approach to alleviate the aforementioned ***–CaCl_(2)·6H_(2)O composite PCM was prepared in the *** composition,phase change latent heat,thermal conductivity,and cemented tailing backfill (CTB) compressive strength of the new material were *** heat transfer characteristics and endothermic effect of the PCM were simulated using Fluent *** results showed the following:(1) The new paraffin–CaCl_(2)·6H_(2)O composite PCM improved the thermal conductivity of native paraffin while avoiding the water solubility of CaCl_(2)·6H_(2)O.(2) The calculation formula of the thermal conductivity of CaCl_(2)·6H_(2)O combined with paraffin was deduced,and the reasons were explained in principle.(3) The“enthalpy–mass scale model”was applied to calculate the phase change latent heat of nonreactive composite PCMs.(4)The addition of the paraffin–CaCl_(2)·6H_(2)O composite PCM reduced the CTB strength but increased its heat absorption *** research can give a theoretical foundation for the use of heat storage backfill in green mines.

关键词： paraffin–CaCl_(2)·6H_(2)O heat transfer simulation heat calculation phase change material-based backfill latent heat of formula

Manganese Dioxide with High Specific Surface Area for Alkaline Battery

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Chemical Research in Chinese Universities 2012年第5期28卷 874-877页

作者： HUANG you-ju LIN Yu-li LI Wei-shan School of Chemistry and Environment Ministry of EducationSouth China Normal UniversityGuangzhou 510006P.R.China Key Laboratory of Electrochemical Technology on Energy Storage and Power Generation of Guangdong Higher Education Institutes Ministry of EducationSouth China Normal UniversityGuangzhou 510006P.R.China Engineering Research Center of Materials and Technology for Electrochemical Energy Storage Ministry of EducationSouth China Normal UniversityGuangzhou 510006P.R.China

The authors reported a facile method for the synthesis of manganese dioxide without any template and catalyst at a low-temperature. The prepared sample was characterized with X-ray diffraction（XRD）, scanning electron microscopy（SEM）, Brunauer-Emmett-Teller（BET） surface analysis, Fourier transform infrared（FTIR） spectrometry, cyclic voltammetry, alternative current（AC） impedance test and battery discharge test. It is found that the prepared sample belongs to α-MnO2 and has a microsphere morphology and a large BET surface area. The electrochemical characterization indicates that the prepared sample displays a larger electrochemical capacitance than the commercial electrolytic manganese dioxides（EMD） in Na2SO4 solution, and exhibits larger discharge capacity than EMD, especially at a high rate discharge condition when it is used as cathode of alkaline Zn/MnO2 battery.

关键词： Manganese dioxide Rate performance Cathode material Alkaline battery

Preparation of mesoporous alumina with large pore size and their supported rhenium oxide catalysts in metathesis of 1-butene and 2-butene to propene

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Journal of Natural Gas Chemistry 2012年第3期21卷 352-359页

作者： Lei Sang Sheng-Li Chen Guimei Yuan Zheng Zhou Rui Li Aicheng Chen Min Zheng ju you State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumBeijing 102249China

Mesoporous γ-aluminas with large pore size （up to 19 nm, denoted as MAI9） are prepared from dispersed pseudo-boehmite using pluronic P123 as template. It is found that these mesoporous alumina supported rhenium oxide catalysts were more active and have far longer working life-span in gas-phase metathesis of 1-butene and 2-butene to propene than rhenium oxide on conventional alumina with small pore size （5 nm）. At 60 ℃ and atmospheric pressure with WHSV = 1 h^-1, the similar stable conversions of butene （ca. 55%） for all the 13 wt% Re207/alumina catalysts were obtained near the chemical equilibrium, and the stable working life-spans of Re2OT/MA19 were far longer than that of Re2O7/A1203, being about 70 h and 20 h, respectively.

关键词： mesoporous alumina rhenium oxide metathesis butene propene

Efficient High Power Ho,Tm:GdVO_(4) Laser

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Chinese Physics Letters 2011年第9期28卷 159-161页

作者： WANG Yue-Zhu ZHU Guo-Li ju you-Lun YAO Bao-Quan National Key Laboratory of Tunable Laser Technology Harbin Institute of TechnologyHarbin 150001

We report a 22.3 W cw diode-pumped cryogenic Ho(0.5at.%),Tm(at.5%):GdVO_(4) laser at a wavelength of 2.05µ*** is pumped by two fiber−coupled laser diodes with a fiber core diameter of 0.4 mm,both of which provide 42 W pump power near 802 nm.A cw output power of 22.3 W was obtained at the pump power of 51.0 W,corresponding to an optical-to-optical conversion efficiency of 43.7%when the ratio of the pump beam to oscillating laser beam in the crystal was∼1.33:*** M^(2) factor was found to be 2.0 under an output power of 16.5 W.

关键词： pump pumped fiber

A Dual-Crystal Cavity Ho,Tm:GdVO4 Laser

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Chinese Physics Letters 2012年第2期29卷 93-94页

作者： ZHU Guo-Li ju you-Lun YAO Bao-Quan WANG Yue-Zhu National Key Laboratory of Tunable Laser Technology Harbin Institute of TechnologyHarbin 150001

We report a 31.2 W cw diode-pumped cryogenic Ho(0.4at.%),Tm(4at.%):GdVO4 laser in a dual-crystal *** pumping sources are two fiber-coupled laser diodes with a fiber core diameter of 0.4 mm,both of which can supply 42W near *** an incident pump power of 70.3W at 802.4nm,a cw output power of 31.2 W at 2.05 μm is attained,corresponding to an optical-to-optical conversion efficiency of 44.4%.The M2 factor is measured as ~1.3 under an output power of 20 W.

关键词： fiber pumped pumping

Turnover of diacylglycerol kinase 4 by cytoplasmic acidification induces vacuole morphological change and nuclear DNA degradation in the early stage of pear self-incompatibility response

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Journal of Integrative Plant Biology 2021年第12期63卷 2123-2135页

作者： Xiao-Xiong Kong Jia-Wei Mei Jing Zhang Xiao Liu ju-you Wu Chun-Lei Wang School of Horticulture and Plant Protection International Research Laboratory of Agriculture and Agri-Product SafetyKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhou 225009China Center of Pear Engineering Technology Research State Key Laboratory of Crop Genetics and Germplasm EnhancementCollege of HorticultureNanjing Agricultural UniversityNanjing 210095China

Pear has an S-RNase-based gametophytic selfincompatibility(SI)*** DNA degradation is a typical feature of incompatible pollen tube death,and is among the many physiological functions of ***,the specific changes that occur in vacuoles,as well as the associated regulatory mechanism in pear SI,are currently *** research in tobacco has shown that decreased activity of diacylglycerol kinase(DGK)results in the morphological change of pollen tube vacuole,whether DGK regulates the pollen tube vacuole of tree plants and whether it occurs in SI response,is currently *** found that DGK activity is essential for pear pollen tube growth,and DGK4 regulates pollen tube vacuole morphology following its high expression and deposition at the tip and shank edge of the pollen tube of ***,incompatible S-RNase may induce cytoplasmic acidification of the pollen tube by inhibiting V-ATPase V0 domain a1 subunit gene expression as early as 30 min after treatment,when the pollen tube is still *** acidification induced by incompatible S-RNase results in reduced DGK4 abundance and deposition,leading to morphological change of the vacuole and fragmentation of nuclear DNA,which indicates that DGK4 is a key factor in pear SI response.

关键词： cytoplasmic acidification diacylglycerol kinase pear self-incompatibility vacuole V-ATPase

Metathesis of 1-butene and 2-butene to propene over Re_2O_7 supported on macro-mesoporous γ-alumina prepared via a dual template method

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Journal of Natural Gas Chemistry 2012年第2期21卷 105-108页

作者： Lei Sang Sheng-Li Chen Guimei Yuan Min Zheng ju you Aicheng Chen Rui Li Lanjing Chen State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumBeijing 102249China

Macro-mesoporous γ-alumina support（MMA） was prepared by a sol-gel route in aqueous medium using pseudo-boehmite as aluminum source and polystyrene microspheres and Pluronic P123 as hard and soft dual templates,*** had a BET specific surface area of about 259 m2 g-1,total pore volume of about 1.61 cm3 g-1,macropore diameter of about 102 nm,and mesopore diameter of about 14 ***2O7/MMA and conventional Re2O7/Al2O3 were prepared by a incipient-wetness impregnation method,and their catalytic performances in the metathesis of 1-butene and 2-butene were tested in a fixed-bed tubular *** result showed that Re2O7/MMA possessed higher activity and far longer working life-span than conventional Re2O7/Al2O3.

关键词： butene metathesis propene rhenium oxide polystyrene microspheres macro-mesoporous alumina

Efficient Tunable Mid-Wave Infrared Laser from 2μm Tm,Ho:YVO_(4)Pumped Gain-Switched Cr^(2+):ZnSe Laser

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Chinese Physics Letters 2011年第5期28卷 140-142页

作者： MENG Pei-Bei YAO Bao-Quan LI Gang ju you-Lun WANG Yue-Zhu National Key Laboratory of Tunable Laser Technology Harbin Institute of TechnologyHarbin 150001

An efficient mid-wave infrared gain-switched Cr^(2+):ZnSe laser pumped by a 2.058μm Tm,Ho:YVO_(4)laser is *** much as 3.86 W output is achieved with the pump power of 13.4 W at puke repetition frequency of 15 kHz,corresponding to the slope efficiency of 30.9%.With a quartz birefringent filter inserted in the laser cavity and by rotating the external angle of the quartz birefringent filter,wavelength tuning range nearly from 2453nm to 2508nm with 5nm linewidth(FWHM)is also obtained.

关键词： ZnSe tuning pumped

Influence of catalyst support structure on ethene/decene metathesis and coke formation over WO_3/SiO_2 catalyst

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Petroleum Science 2013年第1期10卷 112-119页

作者： Zheng Min Chen Sheng-Li Zhang jun-Hui Liu Yan Sang Lei you ju Wang Xiao-Dong State Key Laboratory of Heavy Oil Processing China University of Petroleum

8wt%WO3/SiO2 metathesis （disproportionation） catalysts with different pore structures were prepared by the incipient-wetness-impregnation method. The as-synthesized catalysts were characterized by N2 adsorpfion-desorption, scanning electron microscopy （SEM）, X-ray diffraction （XRD）, UV-visible diffuse reflectance spectroscopy （DRS） and scanning transmission electron microscopy-high-angle annular dark field （STEM HAADF）. The results of STEM HAADF showed that WO3 species were not uniformly distributed on the SiO2 support. The experimental results of 8wt%WO3/SiO2 performance in ethene/decene metathesis revealed that the catalytic effect of 8wt%WO3/SiO2 catalyst and coke formation over it were closely related to the support pore structure： The 8wt%WO3/SiO2 catalyst with a more complicated pore structure showed better catalytic performance but the coke deposition rate was also faster.

关键词： Metathesis WO3/SiO2 catalysts pore structure coke formation

An All Fiber 1.94µm Nanosecond Pulse Laser Amplified by Highly Tm^(3+)-Doped Silicon Fibers

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Chinese Physics Letters 2013年第5期30卷 78-81页

作者： ZHOU Ren-Lai REN Jian-Cun YANG Chao ju you-Lun WANG Yue-Zhu National Key Laboratory of Tunable Laser Technology Harbin Institute of TechnologyHarbin 150080 Naval Aeronautical&Astronautical University Yantai 264000

We present an all-fiber 1.94μm nanosecond pulse laser in master oscillation-power amplifier configuration.A dual-FBGs gain-switched Tm^(3+)-doped fiber laser is built and is used as the seed *** output characteristics of the amplifier are studied at different pulse repetition rates,and the maximum output energy of 500μJ is achieved under incident pump power of 39 *** emitting spectra are checked at 5 and 10 kHz,and no obvious nonlinear effects are observed in the spectrum of the amplified *** beam quality factor is M^(2)=2.1±0.03 measured by the traveling knife-edge method,and the laser beam spot is also monitored by an infrared vidicon camera.

关键词： amplifier fiber switched