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China Petroleum Processing & Petrochemical Technology 2023年第2期25卷 65-73页

作者： hou min Qi Xiaolan Zheng Junlin State Key Laboratory of Green Chemical Engineering and Industrial Catalysis SINOPEC Shanghai Research Institute of Petrochemical Technology Co.Ltd.Shanghai 201208China

Catalytic methylation of toluene with methanol is an important alternative pathway for xylene *** studies have indicated that methanol always undergoes several side reactions on acidic zeolites,resulting in oxygencontaining byproducts such as dimethyl ethers,ketones,and carboxylic ***,the presence and distribution of the oxygenated compounds formed during toluene methylation were firstly examined by systematic chromatographic *** formation mechanisms for the various oxygenates are *** most problematic byproduct is found to be acetic acid,which can lead to inferior product quality and damage downstream units.A feasible solution is presented for oxygenate removal after toluene methylation,in which acetic acid is eliminated by catalytic decomposition into low-boilingpoint acetone over a MgO *** process allows for all of the low-boiling-point oxygenates,including methanol,dimethyl ether,acetone,and butanone,to be removed from the aromatics phase,taking advantage of the temperature of the reaction effluent and standard distillation equipment.X-ray diffraction was used to characterize the crystal phase of the fresh and used MgO decarbonylation catalysts,while thermogravimetry/mass spectrometry and Fourier-transform infrared spectroscopy were applied to investigate the transformation mechanism of acetic acid over the decarbonylation *** insertion and ketonization of acetic acid accounted for the formation and elimination of acetic acid,*** combined methylation/decarbonylation process should enable the production of high-quality xylenes,an important industrial feedstock,by overcoming the main technical obstacles associated with the toluene methylation process.

关键词： xylene catalytic methylation decarbonylation toluene MgO catalyst

Dynamic evolution of Co species and morphological reconstruction on Co-N-C during the nitrate reduction reaction in neutral solution

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Nano Research 2025年第1期18卷 164-172页

作者： yuanlin Fu Xiaoting Yang Ya yu Kang Zhou Xiaoyang Ye Aoxiang Zhang Xiaojiao hou Bingbing Chen Fuqiang Fan yuhang Li yu Fu Department of Chemistry College of SciencesNortheastern UniversityShenyang 110819China Department of Physical Education Shen Yang Institute of Science and TechnologyShenyang 110167China Sungrow Power Supply Co. Ltd.Hefei 230088China

The electrochemical nitrate reduction reaction(eNO_(3)^(-)RR)is considered an effective approach for converting nitrate-containing wastewater to *** adsorption and activation of NO_(3)^(-)is the critical step for many materials and the high energy barrier inhibits the continuation of the reduction *** Co nanoparticles encapsulated in the carbon layer we prepared spontaneously react with NO_(3)^(-)and the resulting Co^(2+)is then reduced by electroreduction to Co^(0),which circulates *** resulted in overcoming the energy input required for NO_(3)^(-)adsorption and conversion,thereby increasing the catalytic *** the same time,the morphology of the catalyst reconstructed from a dodecahedron to an interwoven nanosheet structure and the increased surface area also gives it better *** obtained Co(OH)_(2)@Co-N-C has an excellent eNO_(3)^(-)RR of 2774.7μg·h^(-1)·cm^(-2)with a Faraday efficiency of 81.4%in neutral *** the same time,the material-modified electrode can run stably for more than 100 *** work provides a new idea for the design of Co-based catalysts for eNO_(3)^(-)RR.

关键词： electrochemical nitrate reduction reaction Co-based catalyst dynamic evolution of Co species morphological reconstruction

Integrable System and Motion of Curves in Projective and Similarity Geometries

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Communications in Theoretical Physics 2006年第1期45卷 45-48页

作者： hou yu-Qing Department of Electronics Northwest University Xi＇an 710069 China

Based on the natural frame in the projective geometry, motions of curves in projective geometry are studied. It is shown that several integrable equations including Sawada-Kotera and KK equations arise from motion of plane curves in projective geometries. Motion of space curves described by acceleratlon field and governed by endowing an extra space variable in similarity geometry P^3 is also studied.

关键词： motion of curve similarity geometry projective geometry integrable equation

A Modified Approach for Calculating Dressed Quark Propagator at Finite Chemical Potential

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Communications in Theoretical Physics 2005年第3X期44卷 519-524页

作者： ZONG Hong-Shi CHANG Lei hou Feng-Yao SUN Wei-min LIU yu-Xin Department of Physics Nanjing University Nanjing 210093 China Center for Particle Nuclear Astrophysics Nanjing University Nanjing 210093 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China Department of Physics Peking University Beijing 100871 China

Based on the rainbow approximation of Dyson-Schwinger equation and the assumption that the full inverse quark propagator at finite chemical potential is analytic in the neighborhood of μ = 1, it is proved that the dressed quark propagator at finite chemical potential μ can be written as G0^-1 [μ] =iγ·p↑-A（p↑-^2）＋B（p↑-^2） with p↑-μ= （p↑-p4 ＋iμ）. From the dressed quark propagator at finite chemical potential in Munczek model the bag constant of a baryon and the scalar quark condensate are evaluated. A comparison with previous results is given.

关键词： chemical potential dependence Dyson-Schwinger equation approach

Novel sliding-mode disturbance observer-based tracking control with applications to robot manipulators

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Science China(Information Sciences) 2021年第7期64卷 80-91页

作者： Tairen SUN Long CHENG Zengguang hou min TAN School of Electrical and Information Engineering Jiangsu University State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences School of Artificial Intelligence University of Chinese Academy of Sciences

This paper proposes a sliding-mode disturbance observer(SMDOB)-based tracking controller for a class of nonlinear systems with modeling uncertainties and external disturbances. The SMDOB is constructed using an extended state observer embedded by a filtered sliding mode term. The chattering caused by the sliding mode is compressed by the frequency bandwidths of both the extended state observer and the control system. The novelties of the proposed controller are as follows:(1) The semiglobal asymptotical stability of the combined controller-observer system is guaranteed without the boundedness assumption of the time derivatives of modeling uncertainties;(2) the SMDOB can be implemented with a low complexity because of only three parameters to be tuned. Applications to robot manipulators illustrate the effectiveness of the SMDOB-based tracking control strategy.

关键词： adaptive control robot manipulator disturbance observer sliding mode

Hidden antiunitary symmetry behind ＂accidental＂ degeneracy and its protection of degeneracy

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Frontiers of physics 2018年第1期13卷 211-214页

作者： Jing-min hou Wei Chen School of Physics Southeast University Nanjing 211189 China College of Science Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

In quantum mechanics, accidental degeneracy refers to energy degeneracy that occurs coincidentally, without any protection by symmetry. Here, we prove a theorem stating that any two-fold degeneracy （accidental or not） in a quantum system is protected by a novel hidden symmetry, which can be expressed by an antiunitary operator with its square being -1. In this sense, the so-called accidental degeneracy is not really accidental, and this actually implies a hidden antiunitary symmetry.

关键词： accidental degeneracy hidden symmetry antiunitary symmetry

TGase positively regulates photosynthesis via activation of Calvin cycle enzymes in tomato

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Horticulture Research 2019年第1期6卷 615-625页

作者： min Zhong yu Wang Kun hou Sheng Shu Jin Sun Shirong Guo Key Laboratory of Southern Vegetable Crop Genetic Improvement Ministry of AgricultureCollege of HorticultureNanjing Agricultural University210095 NanjingChina Suqian Academy of Protected Horticulture Nanjing Agricultural University223800 SuqianChina

Transglutaminases(TGases),which are widespread cross-linking enzymes in plants,play key roles in photosynthesis and abiotic/biotic stress responses;however,evidence concerning the genetics underlying how TGase improves the capability of photosynthesis and the mechanism of TGase-mediated photosynthesis are not clear in this crop *** this study,we clarified the function of TGase in the regulation of photosynthesis in tomato by comparing wild-type(WT)plants,tgase mutants generated by the CRISPR/Cas9 system and TGase-overexpressing(TGaseOE)*** results showed that increasing the transcript level of TGase resulted in an enhanced net photosynthetic rate(Pn),whereas the tgase mutants presented significantly inhibited Pns and CO2 assimilation compared with the *** the total RuBisCO activity was not affected by TGase,the initial and activation status of RuBisCO and the activity of RuBisCO activase(RCA)and fructose-1,6-bisphosphatase(FBPase)in TGaseOE plants were significantly higher than that in WT *** for RuBisCO small subunit(RbcS),the transcription levels of Benson–Calvin cycle-related genes were positively related to the endogenous TGase ***,TGaseOE plants had higher protein levels of RuBisCO large subunit(RbcL)and RCA than did WT plants and showed a reduced redox status by enhancing the activity of dehydroascorbate reductase(DHAR)and glutathione reductase(GR),which was compromised in TGasedeficient ***,TGase positively regulated photosynthesis by maintaining the activation states of the Benson–Calvin cycle and inducing changes in cellular redox homeostasis in tomato.

关键词： cycle Benson linking

Ozone decomposition under the irradiation of 253.7 nm in the presence of methyl bromide

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Journal of Environmental Sciences 2000年第3期12卷 266-269页

作者： LI Chao\|min, hou Jian, yu Yong, hou Hui\|qi (Institute of Environmental Science, Fudan University, Shanghai 200433, China) Institute of Environmental Science Fudan University Shanghai 200433 China

In this paper the mechanism and kinetic of ozone decomposition under the irradiation of 253.7 nm UV\|light were studied. The quantum yield of the ozone depletion in the presence of methyl bromide is further determine... 详细信息

关键词： methyl bromide ozone UV

The fundamental plane relation of early-type galaxies:environmental dependence

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Research in Astronomy and Astrophysics 2015年第5期15卷 651-662页

作者： Lei hou yu Wang Department of Astronomy University of Science and Technology of China

Using a sample of 70 793 early-type galaxies from SDSS DR7, we study the environmental dependence of the fundamental plane relation. With the help of the galaxy group catalog based on SDSS DR7, we calculate the fundamental planes in different dark matter halo mass bins for both central and satellite galaxies. We find the environmental dependence of the fundamental plane coefficients is similar in the g, r, i and z bands. The environmental dependence for central and satellite galaxies is significantly different. Although the fundamental plane coefficients for centrals vary systematically with the halo mass, those of satellites are similar in different halo mass bins. The discrepancy between centrals and satellites is significant in small halos, but negligible in the largest halo mass bins. These results remain the same when we only keep red galaxies, or galaxies with b/a 〉 0.6, or galaxies in a specific radius range in the sample. After the correction for the sky background, the results are still similar. We suggest that the different environmental effects of the halo mass on centrals and satellites may arise from their different quenching processes.

关键词： galaxies elliptical and lenticular -- galaxies halo -- galaxies statistics