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Chinese Journal of Chemistry 2015年第7期33卷 792-796页

作者： Yangang bi Wenyuan Zhao ying li Tonglai Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China

The reaction of NiCl2 and 3-hydrazine-4-amino-1,2,4-triazole （Hatr） in the mixed solvent of EtOH and H2O yielded a dimer compound （[Ni2（Hatr）2（H2O）2（EtOH）2Cl2]ClzoEtOH） with water and EtOH molecules coordinated to nickle ions. It crystallized in trigonal space group R-3, a=b=29.67（1） A, c=8.95（7） A, β= 120（1）°, as determined by single-crystal X-ray diffraction. Then, they were fully characterized by the IR spectroscopy, differential scanning calorimetry （DSC）, thermogravimetry （TG）, and elemental analysis.

关键词： dimer compound tridentate ligand nickel X-ray diffraction differential scanning calorimetry

Catalytic Oxidation of Hexanol to Hexanal with H_2O_2 Over P-W Heteropoly Compounds

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Chemical Research in Chinese Universities 2001年第3期17卷 293-298页

作者： ZHOU Guang-dong GUO Xiao-hong liU Yan bi ying-li ZHEN Kai-ji Department of Chemistry Jilin UniversityChangchun 130023P.R.China

The syntheses of Keggin and Dawson-structural phospho-tungsto heteropoly compounds and their Peroxo-derivatives(PCWP), and the catalytic performance over this series of catalysts for the selective oxidation of hexanol to hexylaldehyde are reported. By means of IR, NMR and UV-DRS techniques the catalysts were characterized and a comparison of the structural properties of these catalysts before and after the reaction was made. The correlation between the catalytic performance and the structure of this series of catalysts was discussed as well.

关键词： P-W Heteropoly compound Hexanol Hexanal

biosynthesis of Unsaturated Fatty Acids via Mortierella Isabellina Cultivated in a Medium Containing Butanol

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Chemical Research in Chinese Universities 2002年第3期18卷 303-306页

作者： XIAN Mo YAN Ji chang CHENG Tie xin KANG Yi jian li Wen xing bi ying li ZHEN Kai ji College of Chemistry Jilin UniversityChangchun 130023P.R.China College of Chemistry Northeast Normal UniversityChangchun 130024P.R.China Department of Chemical Engineering Qingdao Chimical Industry InstituteQingdao 266042P.R.China

Mortierella isabellina was found to accumulate large amounts of unsaturated fatty acids when it was grown in a medium containing butanol(5 g/L) and yeast extract(10 g/L) and cultivated at 25 ℃ for 5 d during which additional feeding butanol of 2 g/L was fed after being cultivated for 48 h . The resultant mycelial lipids accounted for 40 1% of the dry mycelia, while about 34% of butanol in the medium was converted. The mycelial lipids contained four kinds of unsaturated fatty acids, i.e ., palmitoleic(4 9%), oleic(54 1%), linoleic(10 4%) and linolenic(5 4%) acids. Those accounted for 74 8% of the total fatty acids. The effects of the culture conditions, such as cultivation temperature, initial pH of the medium and additional feeding butanol in the course of cultivation, on the production of mycelial lipids by M. isabellina were studied.

关键词： Mortierella isabellina Butanol Unsaturated fatty acid biosynthesis

Micro-aluminum powder with bi-or tri-component alloy coating as a promising catalyst:Boosting pyrolysis and combustion of ammonium perchlorate

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Defence Technology（防务技术） 2024年第3期33卷 100-113页

作者： Chao Wang ying liu Mingze Wu Jia li ying Feng Xianjin Ning Hong li Ningfei Wang Baolu Shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A novel design of micro-aluminum(μAl)powder coated with bi-/tri-component alloy layer,such as:Ni-P and Ni-P-Cu(namely,Al@Ni-P,Al@Ni-P-Cu,respectively),as combustion catalysts,were introduced to release its huge energy inside Al-core and promote rapid pyrolysis of ammonium perchlorate(AP)at a lower temperature in aluminized *** microstructure of Al@Ni-P-Cu demonstrates that a three-layer Ni-P-Cu shell,with the thickness of~100 nm,is uniformly supported byμAl carrier(fuel unit),which has an amorphous surface with a thickness of~2.3 nm(catalytic unit).The peak temperature of AP with the addition of Al@Ni-P-Cu(3.5%)could significantly drop to 316.2℃ at high-temperature thermal decomposition,reduced by 124.3℃,in comparison to that of pure AP with 440.5℃.It illustrated that the introduction of Al@Ni-P-Cu could weaken or even eliminate the obstacle of AP pyrolysis due to its reduction of activation energy with 118.28 kJ/*** laser ignition results showed that the ignition delay time of Al@Ni-P-Cu/AP mixture with 78 ms in air is shorter than that of Al@Ni-P/AP(118 ms),decreased by 33.90%.Those astonishing breakthroughs were attributed to the synergistic effects of adequate active sites on amorphous surface and oxidation exothermic reactions(7597.7 J/g)of Al@Ni-P-Cu,resulting in accelerated mass and/or heat transfer rate to catalyze AP pyrolysis and ***,it is believed to provide an alternative Al-based combustion catalyst for propellant designer,to promote the development the propellants toward a higher energy.

关键词： Micro-aluminum powder(μAl) Nano-sized alloy coating Combustion catalyst Ammonium perchlorate Pyrolysis behavior Ignition and combustion

External calibrator in global signal experiment for detection of the epoch of reionization

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Research in Astronomy and Astrophysics 2021年第10期21卷 17-26页

作者： Yan Huang Xiang-Ping Wu Quan Guo Qian Zheng bi-ying li Huan-Yuan Shan Ke-Jia Lee Hai-Guang Xu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China School of Physics and Astronomy Shanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China

We present a conceptual design study of external calibrators in the 21 cm experiment towards detecting the globally averaged radiation of the epoch of reionization(EoR).Employment of external calibrator instead of internal calibrator commonly used in current EoR experiments allows removing instrumental effects such as beam pattern,receiver gain and instability of the system if the conventional three-position switch measurements are implemented in a short time ***,in the new design the antenna system is placed in an underground anechoic chamber with an open/closing ceiling to maximally reduce the environmental effect such as RFI and ground radiation/*** appears that three of the four external calibrators proposed in this paper,including two indoor artificial transmitters and one outdoor celestial radiation(the Galactic polarization),fail to meet our *** motion of the Galactic diffuse emission turns out to be the most probable source as an external calibrator,for which we have discussed the observational strategy and the algorithm of extracting the EoR signal.

关键词： cosmology:observations dark ages reionization radio lines:general methods:observational

Achieving dynamic privacy measurement and protection based on reinforcement learning for mobile edge crowdsensing of IoT

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Digital Communications and Networks 2024年第2期10卷 380-388页

作者： Renwan bi Mingfeng Zhao Zuobin ying Youliang Tian Jinbo Xiong Fujian Provincial Key Laboratory of Network Security and Cryptology College of Computer and Cyber SecurityFujian Normal UniversityFuzhou350117China Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin541004China Faculty of Data Science City University of Macao999078MacaoChina State Key Laboratory of Public big Data College of Computer Science and TechnologyGuizhou UniversityGuiyang550025China

With the maturity and development of 5G field,Mobile Edge CrowdSensing(MECS),as an intelligent data collection paradigm,provides a broad prospect for various applications in ***,sensing users as data uploaders lack a balance between data benefits and privacy threats,leading to conservative data uploads and low revenue or excessive uploads and privacy *** solve this problem,a Dynamic Privacy Measurement and Protection(DPMP)framework is proposed based on differential privacy and reinforcement ***,a DPM model is designed to quantify the amount of data privacy,and a calculation method for personalized privacy threshold of different users is also ***,a Dynamic Private sensing data Selection(DPS)algorithm is proposed to help sensing users maximize data benefits within their privacy ***,theoretical analysis and ample experiment results show that DPMP framework is effective and efficient to achieve a balance between data benefits and sensing user privacy protection,in particular,the proposed DPMP framework has 63%and 23%higher training efficiency and data benefits,respectively,compared to the Monte Carlo algorithm.

关键词： Mobile edge crowdsensing Dynamic privacy measurement Personalized privacy threshold Privacy protection Reinforcement learning

IONIC CONDUCTIVITY AND CATALYTIC PERFORMANCE OF A2BO4/La2O3 CATALYSTS FOR OXIDATIVE COUPliNG OF METHANE

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Journal of Energy Chemistry 1993年第3期 203-211页

作者： bi ying-li XIA Xin-Rui li li-Tao ZHEN Kai-Ji Department of Chemistry, Jilin University Changchun, Jilin 130023

A series of La2O3cartalysts modified by A2BO4compounds with supe-rionic conductivity were prepared. It was observed that the addition of A2BO4compounds to La2O3enhances C2yields, and the C2yields over the modified cat-alysts are intimately related with their conductivities. The effects of A2BO4compounds on the conductivity and catalytic performance were discussed. Onlywhen ion A has high conductivity, can the catalyst show good catalytic perfor-mance. A mechanism for interpreting the significant effects of alkali metals wasproposed.

关键词： IONIC CONDUCTIVITY AND CATALYTIC PERFORMANCE OF A2BO4/La2O3 CATALYSTS FOR OXIDATIVE COUPliNG OF METHANE BO La

Effect　of　Steam　on　the　Oxidative　Coupling　of　Methane　over　La-Ba　System　Catalysts

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Chemical Research in Chinese Universities 1997年第1期13卷 41-45页

作者： PIAO Hong, bi ying li and ZHEN Kai ji (Department of Chemistry, Jilin University, Changchun, 130023)

The influence of steam on catalytic performance for the oxidative coupling of methane(OCM) over Ba 2+ promoted La 2 O 3 catalysts was studied. It was shown that the presence of a suitable amount of steam led to a significant increase of the yield and selectivity to C 2 hydrocarbons, a decrease of selectivity to carbon monoxide and some increase of selectivity to carbon dioxide with increasing the amount of water in the feed was also observed. The activity and selectivity of the catalysts are more sensitive to the effect of steam with the variation of Ba 2+ content in the catalysts at a relatively low temperature(650℃). The comparative experiments for OCM with methane oxygen mixture diluted with nitrogen or steam were carried out in order to investigate the role of steam.

关键词： Effect of steam Methane oxidative coupling La Ba system catalysts

Influence of rare earth oxides on microstructure and mechanical properties of nickel-based superalloys fabricated by high energy beam processing:A review

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Journal of Rare Earths 2024年第9期42卷 1629-1645,I0001页

作者： lianjie bi Hua Yan Peilei Zhang Haichuan Shi Zhiyuan li Ruidi li School of Materials Science and Engineering Shanghai University of Engineering ScienceShanghai201620China College of Agricultural Science and Engineering Hohai UniversityNanjing211100China Department of Mechanics and Maritime Science Chalmers University of TechnologyGothenburSE41296Sweden State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China

In this paper,the effects of rare earth oxides on the micro structure and mechanical properties of nickelbased superalloys prepared by high-energy beam processing technology were critically *** focus is on the optimal amount of rare earth oxides that can produce ideal *** attention was paid to their main strengthening mechanisms,including solid solution strengthening mainly in the form of solid solution dissolved in the nickel-based alloy and improving the microstructure of the alloy by grain refinement or fine grain strengthening produced by homogenizing the distribution phase.Y_(2)O_(3),La_(2)O_(3) and CeO_(2) rare earth oxides can also improve the fluidity of the alloy molten pool and reduce the segregation of alloying *** advantages can significantly improve the mechanical properties of the ***,this paper outlines the future research directions of rare earth oxides,aiming to expand their application potential.

关键词： Rare earths High energy beam Nickel-based superalloys Microstructure Mechanical properties

Feedback of Efficient Shock Acceleration on Magnetic-field Structure Inside Young Type Ia Supernova Remnants

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Research in Astronomy and Astrophysics 2024年第6期24卷 234-244页

作者： Jun-Yu Shen bi-Wen Bao li Zhang Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China Key Laboratory of Statistical Modeling and Data Analysis of Yunnan Province Yunnan UniversityKunming 650091China

Using an effective adiabatic index γ_(eff) to mimic the feedback of efficient shock acceleration,we simulate the temporal evolution of a young type Ia supernova remnant (SNR) with two different background magnetic field(BMF) topologies:a uniform and a turbulent *** density distribution and magnetic-field characteristics of our benchmark SNR are studied with two-dimensional cylindrical magnetohydrodynamic *** γ_(eff)is considered,we find that:(1) the two-shock structure shrinks and the downstream magnetic-field orientation is dominated by the Rayleigh–Taylor instability structures;(2) there exists more quasi-radial magnetic fields inside the shocked region;and (3) inside the intershock region,both the quasi-radial magnetic energy density and the total magnetic energy density are enhanced:in the radial direction,with γ_(eff)=1.1,they are amplified about 10–26 times more than those with γ_(eff)=5/*** in the angular direction,the total magnetic energy densities could be amplified about 350 times more than those with γ_(eff)=5/3,and there are more grid cells within the intershock region where the magnetic energy density is amplified by a factor greater than 100.

关键词： methods:numerical ISM:magnetic fields ISM:supernova remnants magnetohydrodynamics(MHD)