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Quantizations of the W-Algebra W（2, 2）

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Acta Mathematica Sinica,English Series 2011年第4期27卷 647-656页

作者： jun bo LI School of Mathematics and Statistics Changshu Institute of Technology Changshu 215500 P. R. China Department of Mathematics University of Science and Technology of China Hefei 230026 P. R. China Department of Mathematics Tongji University Shanghai 200092 P. R. China

We quantize the W-algebra W（2,2）, whose Verma modules, Harish-Chandra modules, irreducible weight modules and Lie bialgebra structures have been investigated and determined in a series of papers recently.

关键词： Quantization the W-algebra W(2 2) quantum groups Lie bialgebras

Porosity of gas shale:Is the NMR-based measurement reliable?

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Petroleum Science 2022年第2期19卷 509-517页

作者： Peng Zhao bo He bo Zhang jun Liu Key Laboratory of Deep Underground Science and Engineering(Ministry of Education) College of Architecture and EnvironmentSichuan UniversityChengduSichuan 610065China Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengduSichuan 610065China Institute of Science and Technology China Three Gorges CorporationBeijing100038China

Aiming at obtaining an accurate porosity of gas shale,various approaches are ***,nuclear magnetic resonance(NMR),being treated as a kind of new-developed technique,possesses the representative ***,as a booming technique,the reliability of NMR-based porosity of shale is not exactly *** on NMR device,this work measured the porosity of shale experiencing different water soaking time,accordingly,judging the reliability of NMR-based *** indicate the NMR outcomes vary with the water soaking time,making a doubt about the objectivity of NMRbased porosity in reflecting the real shale ***,some supplementary means were adopted to verify the water soaking-induced variation in the pore system of shale sample,which intensities the suspicion if the NMR-based porosity is reliable or *** sum up,this work considers that the NMR-based porosity of shale is not reliable enough when water is used as the ***,this work also offers some suggestions on how to enhance the reliability of NMR-based porosity of shale ***,this work selects a fresh perspective to analyze the NMR approach in determining shale porosity,which is hopefully helpful in promoting the development of NMR technique in the shale-related field.

关键词： Gas shale Low-field NMR Porosity measurement Low-temperature nitrogen adsorption

Microscopic sand production simulation and visual sanding pattern description in weakly consolidated sandstone reservoirs

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Petroleum Science 2022年第1期19卷 279-295页

作者： Chang-Yin Dong bo Zhou Fan-Sheng Huang Lei Zhang Yi-Zhong Zhao Yang Song jun-Yu deng Key Laboratory of Unconventional Oil&Gas Development Ministry of EducationQingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Research Institute of Petroleum Engineering Technology Shengli BranchSINOPECDongying257000ShandongPR China Research Ltd.of Engineering Technology CNPCTianjin345000PR China

To visually describe the sanding pattern,this study constructs a new particle-scale microstructure model of weakly consolidated formation,and develop the corresponding methodology to simulate the sanding process and predict sand cavity *** microstructure model is a particle-objective model,which focuses on the random sedimentation of every sand *** the microstructure,every particle has its own size,sphericity and inclination *** is used to simulate the actual structure of cemented granular materials,which considers the heterogeneity and randomness of reservoir properties,provides the initial status for subsequent sanding *** the particle detachment criteria,the microscopic simulation of sanding can be visually implemented to investigate the pattern and cavity shapes caused by sand *** results indicate that sanding always starts initially from the borehole border,and then extends along the weakly consolidated plane,showing obvious characteristic of *** typical microscopic sanding patterns,concerning pore liquefaction,pseudo wormhole and continuous collapse,are proposed to illustrate the sanding mechanism in weakly consolidated *** nonuniformity of sanding performance depends on the heterogeneous distribution of reservoir properties,such as rock strength and particle ***,the three sanding patterns are verified by visually experimental *** proposed integrated methodology is capable of predicting and describing the sanding cavity shape of an oil well after long-term sanding production,and providing the focus objective of future sand control measure.

关键词： Weakly consolidated reservoir Particle-scale microstructure model Microcosmic sanding process simulation Visual sanding cavity description Sanding prediction Sand control optimization

Stress injuries and autophagy in mouse hippocampus after chronic cold exposure

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Neural Regeneration Research 2017年第3期12卷 440-446页

作者： Ting-ting Qu Jie-xin deng Rui-ling Li Zhan-jun Cui Xiao-qing Wang Lai Wang Jin-bo deng Institute of Neurobiology College of Life ScienceHenan University Nursing College Henan Vocational College of Applied Technology

Cold exposure is an external stress factor that causes skin frostbite as well as a variety of *** might participate in neuroprotection after cold exposure,but its precise mechanism remains *** this study,mice were exposed to 10°C for 7 days and 0–4°C for 30 days to induce a model of chronic cold *** showed that oxidative stress-related c-fos and cyclooxygenase 2 expressions,MAP1LC3-labeled autophagic cells,Iba1-labeled activated microglia,and interleukin-1β-positive pyramidal cells were increased in the hippocampal CA1 *** cold exposure markedly elevated the levels of estrogen in the blood and the estrogen receptor,G protein-coupled receptor *** results indicate that neuroimmunoreactivity is involved in chronic cold exposure-induced pathological alterations,including oxidative stress,neuronal autophagy,and ***,estrogen exerts a neuroprotective effect on cold exposure.

关键词： nerve regeneration chronic cold exposure oxidative stress autophagy microglial cells neuroimmunoreactivity hippocampal CA1 area estrogen neural regeneration

Effect of micro-Al_(2)O_(3) powders on oxidation and corrosion behaviors of low-carbon MgO-C refractories

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Journal of Iron and Steel Research International 2024年第6期31卷 1522-1534页

作者： Yang Chen Zeng-yi Li Hao-bo Tan Yu-ran Fu jun Ding Cheng-ji deng Chao Yu School of Materials Science and Engineering Hunan Institute of TechnologyHengyang 421002HunanChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

To solve the problem of poor high-temperature service performance caused by low carbonization of MgO-C refractories,low-carbon MgO–C refractories with excellent thermal shock,oxidation and corrosion resistances were successfully designed by using SiC whiskers as reinforcing phases and introducing micro-Al_(2)O_(3) powders as *** results indicated that the addition of micro-Al_(2)O_(3) powders optimized the internal structure of the material,like the columnar β-Si_(3)N_(4) with a stepped distribution and the mosaic structure formed between granular and flaky Mg_(2)SiO_(4),which synergistically strengthened and toughened the material and gave the material excellent mechanical properties and thermal shock ***,the cold modulus of rupture and cold crushing strength after thermal shock were increased by 4.1 and 20.3 MPa,***,the addition of micro-Al_(2)O_(3) powders promoted the formation of fine particles of Mg_(2)SiO_(4),MgAl_(2)O_(4) and MgO,as well as a dense protective layer of Mg_(2)SiO_(4) in the material under high-temperature ***,spinel and high-temperature solid solution were formed in the corrosion *** oxidation and corrosion resistances were greatly improved by 41%and 15%,respectively.

关键词： Low-carbon MgO-C refractory Oxidation resistance Corrosion resistance Thermal shock resistance Micro-Al_(2)O_(3)powder

Insect group II chitinase OfChtll promotes chitin degradation during larva-pupa molting

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Insect Science 2021年第3期28卷 692-704页

作者： Ming-bo Qu Shao-Peng Sun Yuan-Sheng Liu Xiao-Rui deng jun Yang Qing Yang School of Bioengineering Dalian University of TechnologyDalianLiaoningChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection and Shenzhen Agricultural Genome Research InstituteChinese Academy of Agricultural SciencesBeijingChina

The insect group ll chitinase(ChtIl,also known as Cht10)is a unique chitinasewith multiple catalytic and chitin-binding *** has been proven genetically to be anessential chitinase for ***,Chtll's role in chitin degradation during insectdevelopment remains poorly *** this knowledge is the key to fullyunderstanding the chitin degradation system in ***,we investigated the roleof OfChtll during the molting of Ostrinia furnacalis,a model lepidopteran pest *** was expressed earlier than OfChtI(OfCht5)and OfChi-h,at both the gene andprotein levels during larva-pupa molting as evidenced by quantitative polymerase chainreaction and western blot analyses.A truncated OfChtII,OfChtII-B4C1,was recombinantlyexpressed in Pichia pastoris cells and purified to *** recombinant OfChtll-B4C1 loosened compacted chitin particles and produced holes in the cuticle surface asevidenced by scanning electron *** synergized with OfChtl and OfChi-h whenhydrolyzing insoluble *** findings suggested an important role for ChtIl duringinsect molting and also provided a strategy for the coordinatdd degradation of cuticularchitin during insect molting by Chtll,Chtl and Chi-h.

关键词： chitin chitinase chitin binding degradation multiple module synergy

Effect of Extrusion Temperature on the Microstructure and Mechanical Properties of Mg–5Al–2Ca Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 1015-1023页

作者： Kun Su Kun-kun deng Fang-jun Xu Kai-bo Nie Li Zhang Xiao Zhang Wei-jian Li College of Materials Science and Engineering Shanxi Key Laboratory of Advanced Magnesium-Based MaterialsTaiyuan University of Technology

In this work, the Mg–5Al–2Ca alloy was extruded at 573, 623 and 673 K, with a ratio of 16：1 and a constant speed of 3 mm/s. Results demonstrate that the Al2Ca particle is formed in Mg–5Al–2Ca alloy. The size, amount and distribution of Al2Ca particles are influenced evidently by extrusion temperature. Unlike previous reports, the intensity of basal texture increases with increasing extrusion temperature, and the reasons are analyzed and given. Even though the average grain size increases as the extrusion temperature increased from 573 to 623 K, the YS, UTS and elongation of asextruded Mg–5Al–2Ca alloy are almost kept the same at 573 and 623 K. The reason is speculated as the balance of grain size, Al2Ca phase and texture at the two temperatures. The work hardening rate depends on extrusion temperature, and the largest θ value of Mg–5Al–2Ca alloy is obtained when the extrusion was performed at 623 K.

关键词： Mg–Al–Ca alloy Extrusion Microstructure Mechanical properties Work hardening

Novel compact and lightweight coaxial C-band transit-time oscillator

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Chinese Physics B 2020年第9期29卷 384-389页

作者： Xiao-bo deng jun-Tao He jun-Pu Ling Bing-Fang deng Li-Li Song Fu-Xiang Yang Wei-Li Xu College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China

Compactness and miniaturization have become increasingly important in the development of high-power microwave *** on this rising demand,a novel C-band coaxial transit-time oscillator(TTO)with a low external guiding magnetic field is proposed and *** proposed device has the following advantages:simple structure,short axial length,high power conversion efficiency,and low external guiding magnetic field,which are of great significance for developing the compact and miniaturized high-power microwave *** application of a shorter axial length is made possible by the use of a transit radiation ***,loading the opening foil symmetrically to both ends of the buncher helps reduce the external magnetic field of the proposed *** traditional foils,the proposed opening foil has a circular-hole;therefore,the electron beam will not bombard the conductive foil to generate *** makes it possible to realize long pulse and high repetition rate operation of the device in future *** numerical calculation and PIC particle simulation,the stability of the intense relativistic electron beam(IREB)and the saturation time of the device are improved by using the conductive *** voltage and current of the diode are 548 kV and 11.4 kA,*** a 0.4-T external guiding magnetic field,a C-band output microwave with a frequency of 4.27 GHz and power of 1.88 GW can be *** power conversion efficiency of the proposed device is about 30%.

关键词： low guiding magnetic field foil focus simple structure short axial length

New influence factor inducing difficulty in selective flotation separation of Cu–Zn mixed sulfide minerals

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 111-115页

作者： Jiu-shuai deng Ying-bo Mao Shu-ming Wen Jian Liu Yong-jun Xian Qi-cheng Feng State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource Engineering Kunming University of Science and Technology

Selective flotation separation of Cu-Zn mixed sulfides has been proven to be difficult. Thus far, researchers have found no satis- factory way to separate Cu-Zn mixed sulfides by selective flotation, mainly because of the complex surface and interface interaction mecha- nisms in the flotation solution. Undesired activation occurs between copper ions and the sphalerite surfaces. In addition to recycled water and mineral dissolution, ancient fluids in the minerals are observed to be a new source of metal ions. In this study, significant amounts of ancient fluids were found to exist in Cu-Zn sulfide and gangue minerals, mostly as gas-liquid fluid inclusions. The concentration of copper ions re- leased from the ancient fluids reached 1.02 × 10-6 tool/L, whereas, in the cases of sphalerite and quartz, this concentration was 0.62 ×10-6 mol/L and 0.44 × 10-6 mol/L, respectively. As a result, the ancient fluid is a significant source of copper ions compared to mineral dissolution under the same experimental conditions, which promotes the unwanted activation of sphalerite. Therefore, the ancient fluid is considered to be a new factor that affects the selective flotation separation of Cu-Zn mixed sulfide ores.

关键词： sulfide minerals flotation separation fluid inclusions