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Thioetherification of isoprene and butanethiol on transition metal phosphides

Journal of Energy Chemistry 2018年第3期27卷 930-939页

作者： Tianyu Ren Mingfeng Li yang chu Jixiang Chen Tianjin Key Laboratory of Applied Catalysis Science and Technology Department of Catalysis Science and Engineering School of Chemical Engineering and Technology Tianjin University Research Institute of Petroleum Processing SINOPEC

Thioetherification between mercaptan and diolefin is an efficient process to remove mercaptans in FCC gasoline at mild condition, during which the selective hydrogenation of diolefin to monoolefin is also expected. Here, Si O2 supported transition metal（Fe, Co, Ni, Mo and W） phosphides were tested for the thioetherification of isoprene and butanethiol on a fixed-bed reactor at 120℃ and 1.5 MPa H2, and their structure before and after reaction was characterized by means of XRD, HRTEM, N2 sorption, CO chemisorption, NH3-TPD, XPS and TG. It was found that, among different metal phosphides, Mo P/Si O2 showed the best performance, and the optimal nominal Mo P loading was 25%. Apart from the nature of metal, the density of metal and acid sites determined the catalyst performance. Metal site was mainly responsible for hydrogenation of isoprene, while acid site dominantly contributed to the thioetherification and the polymerization of olefins. Moreover, a balance between metallic and acidic functions is required to arrive at a desired performance. Excessive metal sites or acid sites led to the over-hydrogenation of isoprene or the severe polymerization of olefins, respectively. 25%Mo P/Si O2 was tested for 37 h time on stream, and butanethiol conversion maintained at 100%; although isoprene conversion remarkably decreased, the selectivity to isopentenes exceeded 80% after reaction for 11 h. We suggest that the deactivation of Mo P/Si O2 is mainly ascribed to the butanethiol poisoning and the carbonaceous deposit, especially the former.

关键词： Transition metal phosphides Bifunctional catalyst Thioetherification Selective hydrogenation Catalyst deactivation

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Mechanisms of aliphatic hydrocarbon formation during co-pyrolysis of coal and cotton stalk

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Chinese Chemical Letters 2016年第10期27卷 1607-1611页

作者： chu-yang Tang De-Xiang Zhang School of Resource and Environmental Engineering Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of EducationEast China University of Science and Technology School of Architecture and Construction University of Science and Technology LiaoNing

Pyrolysis experiments were carried out in a tubular furnace. The characteristics of pyrolysis tar were analyzed by GC/MS. The results indicated that the aliphatic hydrocarbon yield derived from co-pyrolysis tar of cotton stalk and Shenmu coal was obviously higher than that of Shenmu coal pyrolysis under optimum condition. Moreover, microcrystalline cellulose was selected as a model compound and the co- pyrolysis tar of microcrystalline cellulose and Shenmu coal was analyzed for comparison. Base on the experimental results, it was indicated that the alkyl radicals generated from pyrolysis were converted to aliphatic hydrocarbons by radical reactions. Furthermore, the mechanisms of aliphatic hydrocarbon formation were discussed during co-pyrolysis of cotton stalk and Shenmu coal.

关键词： Co-pyrolysisCoalCotton stalkAliphatic hydrocarbonMechanism

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Confinement properties of circular concrete columns wrapped with prefabricated textile-reinforced fine concrete shells

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Frontiers of Structural and Civil Engineering 2023年第10期17卷 1554-1570页

作者： Qin ZHANG Qiao-chu yang Xiang-Lin GU Yong JIANG Hai-yang ZHU College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China Key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education Tongji UniversityShanghai 200092China School of Civil Engineering Suzhou University of Science and TechnologySuzhou 215009China

This paper proposes an innovative column composed of a core column(including both reinforced concrete(RC)and plain concrete(PC)columns)and a prefabricated textile-reinforced fine concrete(TRC)*** study the confinement properties of TRC shells on this novel type of concrete column,20 circular specimens,including 12 PC columns and 8 RC columns,were prepared for axial compressive *** key parameters,including the column size,reinforcing ratio of the carbon textile,concrete strength,and stirrup spacing,were *** results indicated that the compressive properties of the columns were improved by increasing the reinforcing ratio of the textile *** the case of TRC-confined PC columns,the maximum improvement in the peak load was 56.3%,and for TRC-confined RC columns,the maximum improvement was 60.2%.Based on the test results,an analytical model that can be used to calculate the stress–strain curves of prefabricated TRC shell-confined concrete columns has been *** calculated curves predicted by the proposed model agreed well with the test results.

关键词： textile-reinforced fine concrete prefabricated shell confined concrete column confinement properties stress–strain relationship

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Phase field simulation of the 180°domain-switching process in PbTiO_3 single crystal under an antiparallel electric field

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 494-499页

作者： Ping-Li Liu Wu-yang chu Li-Jie Qiao Corrosion and Protection Center Key Laboratory of Environmental Fracture University of Science and Technology Beijing Beijing 100083 China

The process of 180°domain switching in PbTiO_3 single crystal under an antiparallel electric field was investigated by the three-dimensional phase field simulation,especially the effect of electric field on the type and duration of domain *** is found that the polarization reversal of domains takes place under an antiparallel electric field in PbTiO_3 single *** results of the phase field simulation indicate that there is only 90°domain switching under a weak electric *** the rise of the electric field,180°domain switching *** the electric field is strengthened further,90°domain switching disappears and the duration of domain switching is shortened.

关键词： phase field simulation ferroelectric materials electric field domain switching

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Uplifting mechanism of the Tibetan Plateau inferred from the characteristics of crustal structures

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Science China Earth Sciences 2023年第12期66卷 2770-2790页

作者： Xiaofeng LIANG Ling CHEN Xiaobo TIAN yang chu Wentao LI State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBejing 100029China Innovation Academy of Earth Science Chinese Academy of SciencesBejing 100029China School of Earth and Planetary Science University of Chinese Academy of SciencesBeiing 100049China

The Tibetan Plateau has been known for its highest elevation and thickest crust on earth,and become a key region for comprehending the rheology and tectonic evolution of continental plates and associated dynamic *** the past years,numerous geophysical studies have been conducted to explore the deep structure of the Tibetan Plateau,resulting in significant advancements in understanding the formation and growth of the *** paper aims to provide a comprehensive summary and discussion of the geophysical observations and underlying mechanisms of the plateau ***,major relevant tectonic models are reviewed,and the corresponding features of crustal structures and related deformation are ***,recent observations,including the identification of a high-velocity layer in the lower crust of the Lhasa block,the spatial distribution of crustal channel flow,and the decoupling of shallow and deep crustal deformation,are synthesized to gain insights into the crustal structures,and multidisciplinary data are integrated to discuss the potential mechanisms of the plateau ***,some pertinent suggestions are put forward for future research on the Tibetan Plateau.

关键词： Tibetan Plateau Crustal structure Moho doublet Uplift of the plateau Crustal channel flow

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New Simulations of the X-Ray Spectra and Polarizations of Accretion-disk Corona Systems with Various Geometrical Configurations *** Description

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Research in Astronomy and Astrophysics 2022年第8期22卷 140-158页

作者： Xiao-Lin yang Jian-Cheng Wang chu-Yuan yang Yunnan Observatories Chinese Academy of Sciences396 YangfangwangKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Energetic X-ray radiations emitted from various accretion systems are widely considered to be produced by Comptonization in the hot *** corona and its interaction with the disk play an essential role in the evolution of the system and are potentially responsible for many observed ***,many intrinsic properties of the corona are still poorly understood,especially for the geometrical *** traditional spectral fitting method is not powerful enough to distinguish various *** this paper,we intend to investigate the possible configurations by modeling the polarization properties of X-ray *** geometries of the corona include the slab,sphere and *** simulations are implemented through the publicly available code,Lemon,which can deal with the polarized radiative transfer and different electron distributions *** results demonstrate clearly that the observed polarizations are dependent heavily on the geometry of the *** slab-like corona produces the highest polarization degrees(PDs),followed by the cylinder and *** of the interesting things is that the PDs first increase gradually and then decrease with the increase of photon *** slab geometry,there exists a zero-point where the polarization vanishes and the polarization angle(PA)rotates by 90°.These results may potentially be verified by the upcoming missions for polarized X-ray observations,such as IXPE and e XTP.

关键词： relativistic processes polarization X-rays:galaxies scattering radiation mechanisms:non-thermal

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Effect of hydrogen on the friction and wear of Ni-P coatings

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 241-245页

作者： Qing-jun Zhou Jin-xu Li Wu-yang chu Corrosion and Protection Center Key Lab of Environmental Cracking Ministry of Education of China University of Science and Technology Beijing Beijing 100083 China R ＆ D Center Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

The effects of charging and outgassing on the friction and wear of Ni-P amorphous and nanocrystalline coatings were studied under ambient humidity and *** results indicate that hydrogen charging can greatly decrease the volume loss during friction and increase the wear ***,the wear durability can be restored after *** are many cracks on the brittle nanocrystalline before charging,and no crack appears after charging,but there are only a few cracks on the outgassed *** indicates that hydrogen charging can inhibit the crack formation during friction for the brittle Ni-P *** the charged sample,after the surface layer was removed by polishing,the wear track and the friction coefficient are consistent with those of an uncharged *** friction coefficient of the charged amorphous coating is very small within the first 140 s and then increases suddenly to the value corresponding to the uncharged *** absorbed surface layer lubricates the surface,reduces the friction coefficient,and improves the wear durability.

关键词： friction wear hydrogen Ni-P coating nanocrystalline

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MHD simulations of inward shocks in Cassiopeia A

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Research in Astronomy and Astrophysics 2020年第4期20卷 39-43页

作者： chu-Yuan yang Bi-Wen Bao Si-Ming Liu Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033China

Cassiopeia A,the brightest radio supernova remnant(SNR)in the sky,has several unique characteristics in comparison to its *** its radio brightness and prominent soft-concave radio spectrum,itsγ-ray spectrum appears to have a low-energy cutoff near 2 GeV,and it is the only SNR with prominent hard X-ray *** the unusual radio properties may be attributed to strong emission from reverse shocks,the hard X-ray emission has been associated with high-speed inward shocks induced by high density ***,the low-energyγ-ray spectral cutoff could be attributed to slow penetration of lower energy particles accelerated near the inward shocks into high-density emission *** this paper,we carry out magneto-hydrodynamic(MHD)simulations of shocks in Cassiopeia A and demonstrate that its inward shock structure can indeed be reproduced via shock interactions with clumps of gases with a density of 20 cm-3.

关键词： acceleration of particles supernovae:individual(Cassiopeia A) ISM:supernova remnants X-rays:ISM

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Rechargeable solid-state Li-air batteries： a status report

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Rare Metals 2018年第6期37卷 459-472页

作者： chu-Shu yang KangNing Gao XiaoPing Zhang Zhuang Sun Tao Zhang The State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of Sciences Shanghai 200050 China University of Chinese Academy of Sciences Beijing 100049China

The theoretical specific energy of lithium-air battery is as high as 3436 ***^-1, and the possible achieved value may reach 600-700 ***^-l, which enables this energy storage system as an important propulsion power sources for electric vehicles with the driving range of 500-800 km. Currently, Li-air batteries are facing main challenges at stability, efficiency, applicability and safety. In particular, from a practical view of point, the Li-air batteries should be operated directly in ambient air. Solid-state battery system is the best avenue to eventually solve these main issues. At the heart of the solid state, Li-air technology is the solid-state Li^＋-conducting ceramic material. Developing solid-state lithium-air batteries （SSLAB） can solve the problem of applicability fundamentally and circumvent the safety issues completely, and it is also an important avenue to improve the stability of the battery system. In this paper, we provide a systematical review of the progress in the cell construction, the regulation of the electrode/electrolyte interface, the cell assembly, the electrochemical performance and the mechanism for the SSLAB. In every section, the contributions of the recent research progress in the main challenges and the remained questions will be commented. Based on these reviews, we attempt to propose some alternative approaches for the next stage and suggest a development prospective for the SSLAB.

关键词： Solid-state lithium-air batteries Solid-state Li^+-conducting ceramic material Interfacial regulation technology In situ formation of passivation film Frameworks structure

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Roles of Wnt/β-catenin signaling pathway related microRNAs in esophageal cancer

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World Journal of Clinical Cases 2022年第9期10卷 2678-2686页

作者： Chao-yang chu Rui Wang Xian-Li Liu Gastrointestinal Surgery The First Affiliated HospitalCollege of Clinical Medicine of Henan University of Science and TechnologyLuoyang 471003Henan ProvinceChina Oncology Cancer HospitalThe First Affiliated HospitalCollege of Clinical Medicine of Henan University of Science and TechnologyLuoyang 471003Henan ProvinceChina

MicroRNAs(mi RNAs)are endogenous,noncoding,single-stranded small RNAs that regulate expression of tumor suppressor genes and oncogenes and are involved in almost all tumor-related *** RNA dysregulation plays an important role in the occurrence and development of esophageal cancer through specific signal pathways,including the Wnt/β-catenin signaling pathway,and is closely related to the malignant characteristics of esophageal *** interaction between mi RNAs and the Wnt/β-catenin signaling pathway,which is specifically expressed in esophageal cancer tissues,shows potential as a new biomarker and therapeutic *** article reviews the role of mi RNAs related to the Wnt pathway in the carcinogenesis of esophageal carcinoma and its role in Wnt signal *** content of this review can be used as the basis for formulating or improving the treatment strategy of esophageal cancer.

关键词： Wnt signal pathway MicroRNA Esophageal cancer Esophageal cancer tissues

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