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Automorphisms for Some Symmetric Multiparameter Quantized Weyl Algebras and Their Localizations（Dedicated to Professor Yingbo Zhang on her 70th birthday）

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Algebra Colloquium 2017年第3期24卷 419-438页

作者： Xin tang Department of Mathematics & Computer Science Fayetteville State University 1200 Murchison Road Fayetteville NC 28301 USA

We study a family of ＂symmetric＂ multiparameter quantized Weyl alge- bras A-q,A n（K） and some related algebras. We compute the Nakayama automorphism of A-q,A n（K）, give a necessary and sufficient condition for A-q,A n（K） to be Calabi-Yau, and prove that A-q,A n（K） is cancellative. We study the automorphisms and isomorphism problem for A-q,A n（K） and .A-q,A n（K[t]）. Similar results are established for the Maltsiniotis multiparam- eter quantized Weyl algebraA-q,A n（K） and its polynomial extension. We prove a quantum analogue of the Dixmier conjecture for a simple localization （A-q,A n（K））z and determine its automorphism group.

关键词： multiparameter quantized Weyl algebras algebra automorphisms isomor-phism problem quantum Dixmier conjecture

C^(0) conjugacy between PM functions with nonmonotonicity height equal to 1

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Science China Mathematics 2021年第9期64卷 1993-2006页

作者： Xiao tang School of Mathematics Sichuan UniversityChengdu610064China

In this paper,a topological classification of piecewise monotone functions(abbreviated as PM functions)with nonmonotonicity height equal to 1 which are strictly increasing on their characteristic intervals and have fi... 详细信息

关键词： topological conjugacy PM function nonmonotonicity height piecewise construction

Characteristics of fluidization and dry-beneficiation of a wide-size-range medium-solids fluidized bed

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International Journal of Mining Science and Technology 2017年第3期27卷 467-471页

作者： tang Ligang Coal Mining and Designing Department Tiandi Science & Technology Co. Ltd. Beijing 10001.3 China

Wide-size-range medium-solids are used in a modularized coal beneficiation demonstration system with a gas-solid fluidized bed. The characteristics of fluidization and dry-beneficiation of the medium solids were studied. The numerical simulation results show that 0.15–0.06 mm fine magnetite powder can decrease the disturbances caused by the bubbles. This is beneficial to the uniformity of the gas-solid interactions and thus to the uniformity and stability of the bed density and height. The experimental results show that, with an increase in the fine coal content in medium solids, both the fluidization quality and the beneficiation performance of the bed decreased gradually. When the fine coal content was no more than 13%, a relatively high superficial gas velocity increased the beneficiation efficiency. When the content was more than 13%, part of the fine coal was separated, leading to product layers. The separation efficiency was therefore gradually decreased. The models for predicting the bed density standard deviation and the probable error, E, value were both proposed. The E value can reach to 0.04–0.07 g/cm^3 under the optimized experimental parameters. This work provides a foundation for the adjustment of the bed density and the separation performance of the modularized 40–60 ton per hour dry coalbeneficiation industrial system.

关键词： Medium solids Wide size range Gas-solid fluidized bed Fluidization Dry beneficiation of coal

Reductive smelting of spent lead–acid battery colloid sludge in a molten Na_2CO_3 salt

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 798-803页

作者： Yu-jie Hu Chao-bo tang Mo-tang tang Yong-ming Chen School of Metallurgy and Environment Central South University School of Metallurgy Engineering Hunan University of Technology

Lead extraction from spent lead–acid battery paste in a molten Na2CO3 salt containing Zn O as a sulfur-fixing agent was studied. Some influencing factors, including smelting temperature, reaction time, Zn O and salt dosages, were investigated in detail using single-factor experiments. The optimum conditions were determined as follows: T = 880°C; t = 60 min; Na2CO3/paste mass ratio = 2.8:1; and the Zn O dosage is equal to the stoichiometric requirement. Under the optimum conditions, the direct recovery rate of lead reached 98.14%. The results suggested that increases in temperature and salt dosage improved the direct recovery rate of lead. XRD results and thermodynamic calculations indicated that the reaction approaches of lead and sulfur were Pb SO4→Pb and Pb SO4→Zn S, respectively. Sulfur was fixed in the form of Zn S, whereas the molten salt did not react with other components, serving only as a reaction medium.

关键词： lead–acid batteries molten salts lead smelting des

Optimization strategy in end milling process for high speed machining of hardened die/mold steel

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Journal of University of Science and Technology Beijing 2006年第3期13卷 240-243页

作者： Ying tang Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China

An optimization strategy for high speed machining of hardened die/mold steel based on machining feature analysis was studied. It is a further extension of the previously presented study on the thermal mechanism of end milling and constant cutting force control. An objective function concerning machining cost and associated optimization algorithm based on machining time and cutting length calculation was proposed. Constraints to satisfy specific machining strategies when high speed machining the hardened die/mold steel, trochoid tool path pattern in slot end milling to avoid over-heat and feed rate adaptation to avoid over-load, were also discussed. As a case study, the tool selection problem when machining a die part with multiple machining features was investigated.

关键词： optimization algorithm hardened die/mold steel machining cost machining feature

Transforming alkanes to alkylsilanes

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Science Bulletin 2016年第12期61卷 914-916页

作者： Yong tang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

Alkanes are the simplest organic molecules that contain only carbon–carbon single bond and carbon–hydrogen *** chemical bonds are very strong,making alkanes the least reactive organic *** the other hand,alkanes are the major components of petroleum and natural *** and renewable biomass are also sources of alkanes,which are produced through gasification of such materials to syngas（a mixture of CO and H2）followed

关键词：烷烃硅烷烷基转化有机分子组成部分碳-碳天然气

Controlled synthesis of one-dimensional segmented heteronanostructures

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Science China Materials 2024年第8期67卷 2715-2716页

作者： Zhiyong tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China

Telluride materials possess distinctive advantages,including the high theoretical volume capacity and electrical conductivity,rendering them promising candidates for a range of energy storage and optoelectronic applications[1].Heterogeneous compositions and interfaces in heteronanostructures have significant implications on the electron transport,magnetic coupling,and phonon scattering,thereby promoting the performances in photocatalysis,and thermoelectrics[2].

关键词： synthesis rendering thereby

Overexpression of Arabidopsis thaliana malonyl-CoA synthetase gene enhances cold stress tolerance by activating mitogen-activated protein kinases in plant cells

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Journal of Forestry Research 2021年第2期32卷 741-753页

作者： Wei tang Anna Y.tang College of Arts and Science East Carolina UniversityGreenvilleNC 27858USA 101 Stadium Drive University of North Carolina at Chapel HillChapel HillNC 27514USA

Malonyl-CoA synthetases may modulate cell responses to abiotic stress by regulating stress-related signaling transduction pathways or activating expression of transcription ***,the molecular mechanism of cold stress tolerance enhanced by malonyl-CoA synthetase is not fully ***,we report that overexpression of the Arabidopsis thaliana malonyl-CoA synthetase gene AAE13.1 resulted in increased cell viability and growth rate and decreased thiobarbituric acid reactive substances under cold stress in rice(Oryza sativa L.),tobacco(Nicotiana tabacum),and slash pine(Pinus elliottii Engelm.).AAE13.1 was associated with cold stress tolerance by increasing the activity of ascorbate peroxidase,catalase,polyphenol oxidase,and peroxidase and the accumulation of acid phosphatase and alkaline *** six rice mitogenactivated protein kinase(MAPK)genes examined,AAE13.1 overexpression increased the expression of OsMAPK genes during cold ***13.1 activated expression of stressresponse genes OsMAPK1,OsMAPK2,and OsMAPK3,indicating that AAE13.1 enhances cold stress tolerance by regulating expression of MAPK genes in plant *** results increase our understanding of cold stress tolerance in species of monocotyledons,dicotyledons,and gymnosperms.

关键词： Cold stress Malonyl-CoA synthetase gene MAPK transcription factor Phosphatase Pinus

Overexpression of Arabidopsis thaliana cysteine2/histidine2-type transcription factor 6 gene enhances plant resistance to a bacterial pathogen

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Journal of Forestry Research 2021年第1期32卷 249-262页

作者： Wei tang Anna Y.tang College of Arts and Science East Carolina UniversityGreenvilleNC 27858USA 2 Stadium Drive University of North Carolina at Chapel HillChapel HillNC 27514USA

Transcription factors can be used to engineer plants for enhanced ***,the mechanism(s)by which the C2H2-type zinc fi nger transcription factor enhances pathogen resistance in cells is not fully ***,Agrobacterium tumefaciens carrying the gene for Arabidopsis thaliana cysteine2/histidine2-type transcription factor 6(ZAT6)was used to engineer rice(Oryza sativa L.),cotton(Gossypium hirsutum L.),and slash pine(Pinus elliottii Engelm.)to generate transgenic cell *** cells were then inoculated with the pathogenic bacterium Pseudomonas *** to the control,cell viability of transgenic cells increased 39–47%and growth rate increased 9–15%by 7 days after inoculation in rice,cotton and slash *** phosphatase activity and alkaline phosphatase activity and transcript levels of Ca 2+-dependent protein kinase genes OsCPK1,OsCPK2,OsCPK6,and OsCPK8 and mitogen-activated protein kinase genes OsMAPK1,OsMAPK2,OsMAPK3,and OsMAPK8 increased signifi cantly in transgenic rice cells by 3 day after inoculation,and extracellular pH had decreased by 10–14%by 96 min after inoculation in transgenic rice,cotton and slash pine *** results suggest that ZAT6 enhances *** resistance in plant cells by modulating transcription of CPK and MAPK and oxidase activity.

关键词： Ca^2+-dependent protein kinase Mitogenactivated protein kinase Oxidase Pathogen Pinus