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华电技术 2013年第6期35卷 85-88页

作者： yang yong liu lei yu chao China Huadian EngineeringCorporation Limited Beijing 100035 China

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期 88-99页

作者： yu-Jing Weng Zhao-Ying Ding Ying-chao Li yuan-Feng Wu yuan-yang Xu Rui Chen Xiao-lei Zhao Hai-yong Wang Da-lei Zhang yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

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GaN-based LEDs for light communication

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Science China(Physics,Mechanics & Astronomy) 2016年第10期59卷 1-10页

作者： LiXia Zhao Shichao Zhu ChunHui Wu chao yang ZhiGuo yu Hua yang lei liu Semiconductor Lighting Research and Development Center Institute of Semiconductors Chinese Academy of Sciences

Rapid improvement in the efficiency of GaN-based LEDs not only speed up its applications for general illumination, but offer the possibilities for data transmission. This review is to provide an overview of current progresses of GaN-based LEDs for light communications. The modulation bandwidth of GaN-based LEDs has been first improved by optimizing the LED epilayer structures and the modulation bandwidth of 73 MHz was achieved at the driving current density of 40 A/cm2 by changing the multi-quantum well structures. After that, in order to increase the current density tolerance, different parallel flip-chip micro-LED arrays were fabricated. With a high injected current density of ~7900 A/cm2, a maximum modulation bandwidth of ~227 MHz was obtained with optical power greater than 30 mW. Besides the increase of carrier concentrations, the radiative recombination coefficient B was also enhanced by modifying the photon surrounding environment based on some novel nanostructures such as resonant cavity, surface plasmon, and photonic crystals. The optical 3 dB modulation bandwidth of GaN-based nanostructure LEDs with Ag nanoparticles was enhanced by 2 times compared with GaN-based nanostructure LEDs without Ag *** results demonstrate that using the QW-SP coupling can effectively help to enhance the carrier spontaneous emission rate and also increase the modulation bandwidth for LEDs, especially for LEDs with high intrinsic IQE. In addition, we discuss the progress of the faster color conversion stimulated by GaN-based LEDs.

关键词： GaN-based LEDs modulation bandwidth carrier concentration radiative recombination coefficient

Combinatorial reasoning-based abnormal sensor recognition method for subsea production control system

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Petroleum Science 2024年第4期21卷 2758-2768页

作者： Rui Zhang Bao-Ping Cai chao yang yu-Ming Zhou yong-Hong liu Xin-yang Qi College of Mechanical and Electronic Engineering China University of PetroleumQingdao266580ShandongChina BGP Inc. China National Petroleum CorporationZhuozhou072750HebeiChina

The subsea production system is a vital equipment for offshore oil and gas *** control system is one of the most important parts of *** and processing the signals of subsea sensors is the only way to judge whether the subsea production control system is ***,subsea sensors degrade rapidly due to harsh working environments and long service *** leads to frequent false alarm incidents.A combinatorial reasoning-based abnormal sensor recognition method for subsea production control system is proposed.A combinatorial algorithm is proposed to group *** long short-term memory network(LSTM)is used to establish a single inference model.A counting-based judging method is proposed to identify abnormal *** data from an offshore platform in the South China Sea is used to demonstrate the effect of the proposed *** results show that the proposed method can identify the abnormal sensors effectively.

关键词： Abnormal sensor Combinatorial algorithm Fault identification Subsea production control system

Effects of internals on phase holdup and backmixing in a slightly-expanded-bed reactor with gas–liquid concurrent upflow

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2273-2283页

作者： Kang yu WeijieWang Tao Zhang yumei yong chao yang CAS Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China 3 PetroChina Petrochemical Research InstituteBeijing 102206China

Five different internals were designed,and their effects on phase holdup and backmixing were investigated in a gas–liquid concurrent upflow reactor where the spherical alumina packing particles of three diameters(3.0,4.5 and6.0 mm)were slightly expanded under the conditions of varied superficial gas velocities(6.77×10-2-3.61×10-1 m·s-1)and superficial liquid velocities(9.47×10-4-2.17×10-3 m·s-1).The experimental results show that the gas holdup increases with the superficial gas velocity and particle size,opposite to the variational trend of liquid *** an internal component is installed amid the upflow reactor,a higher gas holdup,a less liquid holdup and a larger Peclet number characterizing the weaker backmixing are obtained compared to those in the bed without internals under the same operating ***,the minimal backmixing is observed in the reactor equipped with the internals with a novel multi-step ***,empirical correlations were proposed for estimating gas holdup,liquid holdup and Peclet number with the relative deviations within 11%,12%and 25%,respectively.

关键词： Internals Phase holdup Backmixing Slightly-expanded-bed reactor Multiphase flow Hydrodynamics

Probing the effect of nitrate anion in CAN: An additional opportunity to reduce the catalyst loading for aerobic oxidations

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Chinese Chemical Letters 2023年第10期34卷 159-162页

作者： Ying Chen chao Chen yonghong liu lei yu School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Catalyzed by cerium ammonium nitrate(CAN),the oxidative cracking reaction of alkenes occurred to produce carbonyls in good yields under mild *** reaction employed molecular oxygen(O_(2))as the safe and clean *** catalyst dosage was reduced to as low as 0.5 mol%,while no additive was ***,it may afford a generally green synthetic approach for introducing oxygen into organic molecules as well as the biomass degradation and the resource recycling from the C=C bond-containing waste polymers.X-ray photoelectron spectroscopy(XPS)analysis and control experiments demonstrated that the process proceeded via a single electron transfer(SET)reaction-initiated free radical reaction *** the process,both Ce and NO_(3)−acted as the oxygen carrier to promote the oxidation *** application of the abundantly existed nitrate in CAN was found to be the key for reducing the catalyst loading.

关键词： Nitrate Alkene Oxidation C=C bond cleavage Ceric Molecular oxygen

Surface decarburization characteristics and relation between decarburized types and heating temperature of spring steel 60Si2MnA

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 720-724页

作者： chao-lei Zhang Le-yu Zhou Ya-zheng liu School of Materials Science and Engineering University of Science and Technology Beijing

The characteristics of complete and partial decarburizations in spring steel 60Si2MnA were systematically investigated, including the microstructure, the hardness gradient, and the formation mechanism. The relation between decarburized types and heating temperature of the steel was comprehensively discussed. It is found that heating temper- ature has an important influence on the decarburized types. With the rise of heating temperature, the decarburized types change from no decarburization to complete decarburization, complete and partial decarburizations, partial decarburiza- tion, and no decarburization.

关键词： spring steel decarburization temperature microstructure hardness

The direct synthesis of Ni/SAPO-11 hydroisomerization catalyst via a novel two-step crystallization strategy

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Petroleum Science 2022年第5期19卷 2448-2459页

作者： Wei-Long Zhan yu-chao Lyu Xin-Mei liu lei Fan Fu-Rang Li Ye yang State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao266580China College of Chemical Engineering China University of PetroleumQingdao266580China

The Ni/SAPO-11 catalyst used for n-hexane hydroisomerization was prepared via a novel two-step crystallization *** involves introduction of nickel salt into the pre-crystalized system of SAPO-11 by grinding followed by a second crystallization *** extra solvent is introduced during the whole synthesis procedure which reduces waste liquid emissions *** importantly,interaction between nickel and support is effectively regulated by the novel method to achieve a well dispersed nickel species and inhibit formation of inert nickel spinel *** environments of framework Si are tuned to enhance surface acidity of the Ni/SAPO-11 *** also shows smaller particle size which favors fast diffusion of reactants and *** into the two-step crystallization indicate that accumulation of SAPO-11 precursors in the pre-crystallization stage,pH regulation by nickel salt and structural directing effect of Ni2+during the second crystallization period account for the rapid crystal growth and smaller particle size of the Ni/SAPO-11 *** the unique features endow the Ni/SAPO-11 catalyst higher activity and isomers selectivity than the Pt/SAPO-11 catalyst in n-hexane hydroisomerization.

关键词： Two-step crystallization Hydroisomerization catalyst Nickel SAPO-11 Synthesis

Revisiting gamma-ray burst afterglows with time-dependent parameters

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Research in Astronomy and Astrophysics 2018年第2期18卷 53-72页

作者： chao yang yuan-Chuan Zou Wei Chen Bin Liao Wei-Hua lei yu liu School of Physics Huazhong University of Science and Technology

The relativistic external shock model of gamma-ray burst （GRB） afterglows has been estab- lished with five free parameters, i.e., the total kinetic energy E, the equipartition parameters for electrons ee and for the magnetic field eB, the number density of the environment n and the index of the power- law distribution of shocked electrons p. A lot of modified models have been constructed to consider the variety of GRB afterglows, such as： the wind medium environment by letting n change with radius, the energy injection model by letting kinetic energy change with time and so on. In this paper, by as- suming all four parameters （except p） change with time, we obtain a set of formulas for the dynamics and radiation, which can be used as a reference for modeling GRB afterglows. Some interesting results are obtained. For example, in some spectral segments, the radiated flux density does not depend on the number density or the profile of the environment. As an application, through modeling the afterglow of GRB 060607A, we find that it can be interpreted in the framework of the time dependent parameter model within a reasonable range.

关键词： (stars:) gamma.ray burst: general -- methods: analytical

Synthesis of selenium-doped carbon from glucose:An efficient antibacterial material against Xcc

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Chinese Chemical Letters 2020年第7期31卷 1887-1889页

作者： Hongen Cao yufan yang Xijun Chen Jian liu chao Chen Shuzhong yuan lei yu School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China School of Horticulture and Plant Protection Yangzhou UniversityYangzhou 225009China State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationResearch and Development Center for Fine ChemicalsGuizhou UniversityGuiyang 550025China Sichuan Selewood Technology Company Limited.Chengdu 610218 China Department of Applied Chemistry Faculty of EngineeringKyushu Institute of TechnologyKitakyushu 804-8550Japan

Se/C as a novel carbon-based biomaterial was prepared by using cheap and abundant glucose as the carbon *** was highly active and could well restrain Xanthomonas campestris ***(EC50=4.7403 μg/mL),a very harmful germ causing the devastating cabbage black rot disease and resulting in huge economic *** a type of carbon material insoluble in wate r,Se/C is bio-compatible and can adhere onto the leaves of the plants to allow a slow and sustained release of its efficacy,affording an efficient method for the cabbage black rot disease prevention and *** work as the first report on the bioactivity studies of Se/C significantly expands the application scopes of the selenium-containing materials and may draw continuous attentions from a broad field.

关键词： Carbon materials Biomaterials Amorphous materials Selenium Bioactivity Cabbage black rot disease