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Kinetics and Mechanism of the Photo-oxidation of Thiophene by O_2 Adsorbed on Molecular Sieves

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Chemical Research in Chinese Universities 2008年第1期24卷 96-100页

作者： zhao di-shun LI Fa-tang ZHOU Er-peng SUN Zhi-min College of Chemical and Pharmaceutical Engineering Hebei University of Science and Technology Shijiazhuang 050018 P. R. China School of Chemical Engineering Tianjin University Tianjin 300072 P. R. China College of Science Hebei University of Science and Technology Shijiazhuang 050018 P. R. China

Photochemical oxidation of thiophene in n-octane/water extraction system using O2 as oxidant was studied. The reaction mechanism ofthiophene oxidation was proposed. Results obtained here can be used as the reference for the oxidative desulfurization of gasoline because thiophene is one of the main components containing sulfur in fluid catalytic cracking gasoline. Thiophene dissolved in n-octane was photodecomposed and removed into the water phase at ambient temperature and atmospheric pressure. A 500 W high-pressure mercury lamp （main wave length 365 nm, 0.22 kW/m） was used as light source for irradiation, and air was introduced by a gas pump to supply O2. Thiophene can be photo-oxidized to sulfone, oxalic acid, SO4^2-, and CO2. The desulfurization yield of thiophene in n-octane is 58.9% under photo-irradiation for 5 h under the conditions of air flow at 150 mL/min and V（water）：V（n-octane）=1：1. It can be improved to 92.3% by adding 0.15 g zeoliteartificial into 100 mL reaction system, which is the adsorbent for O2 and thiophene. And under such conditions, the photo-oxidation kinetics of thiophene with O2/zeoliteartificial is first-order with an apparent rate constant of 0.5047 h^-1 and a half-time of 1.37 h. The sulfur content can be depressed from 800 μL/L to less than 62 μL/L.

关键词： Thiophene Desulfurization Photo-oxidation kinetics Mechanism Photo-oxidation product Molecular sieve

Progress in preparation of AlN-reinforced magnesium matrix composites:A review

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China Foundry 2024年第1期21卷 1-10页

作者： Lu Chen Shu-lin Lü di-jia zhao Wei Guo Jian-yu Li Shu-sen Wu State Key Lab of Materials Processing and die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

As a ceramic material,AlN has very good thermophysical and mechanical *** addition,AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of ***,AlN is an ideal reinforcement for magnesium matrix composites(MMCs),and is attracting increasing *** review addresses the development of preparation technologies for AlN-reinforced Mg matrix *** mainstream preparation techniques include stir casting,melt infiltration,powder metallurgy,and in-situ *** addition,the advantages and disadvantages of these techniques are analyzed in depth,and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration.

关键词： AlN MMCs preparation thermophysical property mechanical property

A core-satellite-like nanoassembly reverses a decisive tyrosine hydroxylase loss in degenerative dopaminergic neurons

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Nano Research 2023年第7期16卷 9835-9847页

作者： Ke Yao Jiamin Gan di zhao Mingding Li Xiaoquan Shen Yumin Yang Peijian Feng Qundong Shen Department of Polymer Science&Engineering and Key Laboratory of High-Performance Polymer Materials and Technology of MOE School of Chemistry&Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory for Neuroregeneration of Jiangsu Province and Ministry of Education Co-innovation Center of NeuroregenerationNantong UniversityNantong 226001China Medical School of Nanjing University Nanjing 210008China State Key Laboratory of Analytical Chemistry for Life Science Nanjing UniversityNanjing 210023China

In recent years,neurodegenerative diseases,such as Parkinson’s or Alzheimer’s diseases,are rapidly rising in *** main hallmark of Parkinson’s disease is the falling levels of neurotransmitter dopamine in the mid-brain with dopaminergic neurons *** therapeutic solutions,including drugs,deep brain stimulation,and cell transplantation,can only alleviate the symptoms of Parkinson’s *** is a tremendous challenge to reverse the function degeneration of the crucial dopaminergic ***,we develop a core-satellite-like nanoassembly(PDA-AFn(by integrating polydopamine nanoparticles and apoferritin))to raise the expression of tyrosine hydroxylase(TH),a rate-limiting enzyme in the formation of the *** components in the nanoassembly could cooperate with each other,not only elaborately regulate the iron homeostasis and redox microenvironment,but also utilize excessive reactive oxygen species(ROS)and iron ions in the damaged neurons to supply extra dopamine and enhance TH activity,and consequently restore the function of the degenerated ***,the nanoassembly-treatment relieves the dyskinesia and dramatical increases the tyrosine hydroxylase and dopamine level in the midbrain of Parkinson’s disease model *** is an explicit yet inspiring advance in treatment of the neurodegeneration.

关键词： neurodegenerative disease dopaminergic neurons tyrosine hydroxylase apoferritin Parkinson’s disease

Facile Aldol Reaction Between Unmodified Aldehydes and Ketones in Bronsted Acid Ionic Liquids

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Chemical Research in Chinese Universities 2007年第5期23卷 549-553页

作者： LIU Bao-you zhao di-shun XU Dan-qian XU Zhen-yuan Key Laboratory of Contaminant Controlling in Biology of Hebei Province College of Environmental Science and Engineering Hebei University of Science and Technology Shijiazhuang 050018 P. R. China State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Zhejiang University of Technology Hangzhou 310014 P. R. China Pharmaceutical Engineering Research Centre of Hebei Province College of Chemical and Pharnmceutical Engineering Hebei University of Science and Technology Shijiazhuang 050018 P. R. China

A series of condensation reactions of unmodified ketones and aromatic aldehydes to prepare α,β-unsaturated carbonyl compounds by means of Aldol reactions in Bronsted acid ionic liquids（BAILs）was explored.1-Butyl-3-methylimidazolium hydrogen sulphate（BMImHSO4）acting as an effective media and catalyst in aldol reactions was compared with other BAILs,with the advantages of high conversion and *** product was easily isolated and the left ionic liquid can be readily recovered and reused at least 3 times with almost the same *** scope and limitation of the present method were explored and the possible catalytic mechanism was speculated.

关键词： Bronsted acid ionic liquid(BAIL) Aldol reaction α,β-Unsaturated carbonyl compound

Fractal characteristic evaluation and interpolation reconstruction for surface topography of drilled composite hole wall

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Frontiers of Mechanical Engineering 2021年第4期16卷 840-854页

作者： Yu YANG Hui CHENG Biao LIANG Guoyi HOU di zhao Chun LIU Kaifu ZHANG School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China

In this paper,an improved fractal interpolation model is proposed to reconstruct the surface topography of composite hole *** model adopts the maximum positive deviations and maximum negative deviations between the measured values and trend values to determine the contraction *** profiles in 24 directions are *** parameters are calculated to evaluate the measured surface *** maximum and minimum fractal dimension of the hole wall are 1.36 and 1.07,whereas the maximum and minimum fractal roughness are 4.05 x 10-5 and 4.36 x 10-10 m,*** on the two-dimensional evaluation results,three-dimensional surface topographies in five typical angles(0°,45°,90°,135°,and 165°)are reconstructed using the improved *** parameter Ds and statistical parameters Sa9 Sq,and Sz are used to evaluate the reconstructed *** error of Ds,Sa,Sq,and Sz between the measured surfaces and the reconstructed surfaces are 1.53%,3.60%,5.60%,and 9.47%,*** with the model in published literature,the proposed model has equal reconstruction effect in relatively smooth surface and is more advanced in relatively rough *** results prove that the proposed model for calculating contraction factors is more reasonable.

关键词： surface topography fractal evaluation fractal interpolation reconstruction composite

Effect of micro-alloying Ca on microstructure,texture and mechanical properties of Mg-Zn-Y-Ce alloys

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Progress in Natural Science:Materials International 2020年第2期30卷 213-220页

作者： Xiaofang Liu Xianhua Chen Jianbo Li Chunquan Liu di zhao Renju Cheng Fusheng Pan International Joint Laboratory for Light Alloys(MOE) College of Materials Science and EngineeringChongqing University National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing Academy of Science and Technology Shenyang Notional Laboratory for Materials Science Chongqing University

Microstructure,texture and mechanical properties of Mg-5 Zn-0.3 Y-0.2 Ce alloys with the addition of trace xCa(x=0,0.3,0.6 wt%) were systematically investigated in this *** results revealed that more secondary eutectic phases and smaller grain size of as-cast microstructure could be found with increasing Ca *** hot extrusion,the Ca-free alloy showed a uniformly recrystallized grain structure,while the Ca-containing alloys possessed a bimodal grain structure composed of fine dynamic recrystallized(DRXed) grains with a size of several microns and un-recrystallized coarse *** analysis showed that the three extruded alloys had a fiber texture of(0001) basal plane aligned with the extrusion *** intensity of the DRXed region was weaker than the deformed *** extruded alloy with the addition of 0.6 wt% Ca exhibited the highest yield strength of 321 MPa due to the smallest DRXed grain size,the deformed region with strong basal texture and dense nanosized precipitates.

关键词： Ca micro-alloying Extrusion Microstructure Texture Mechanical properties Mg–Zn–Y–Ce alloy

Dominant changes in the breast muscle lipid profiles of broiler chickens with wooden breast syndrome revealed by lipidomics analyses

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Journal of Animal Science and Biotechnology 2022年第6期13卷 1703-1713页

作者： Ranran Liu Fuli Kong Siyuan Xing Zhengxiao He Lu Bai Jiahong Sun Xiaodong Tan di zhao Guiping zhao Jie Wen Institute of Animal Sciences Chinese Academy of Agricultural SciencesState Key Laboratory of Animal NutritionKey Laboratory of Animal(Poultry)Genetics Breeding and ReproductionMinistry of AgricultureBeijingChina

Background: Chicken is the most consumed meat worldwide and the industry has been facing challenging myopathies. Wooden breast(WB), which is often accompanied by white striping(WS), is a serious myopathy adversely affecting meat quality of breast muscles. The underlying lipid metabolic mechanism of WB affected broilers is not fully ***: A total of 150 chickens of a white-feathered, fast-growing pure line were raised and used for the selection of WB, WB + WS and control chickens. The lipids of the breast muscle, liver, and serum from different chickens were extracted and measured using ultra performance liquid chromatography(UPLC) plus Q-Exactive Orbitrap tandem mass spectrometry. In the breast, 560 lipid molecules were identified. Compared to controls, 225/225 of 560 lipid molecules(40.2%) were identified with differential abundance(DA), including 92/100 significantly increased neutral lipids and 107/98 decreased phospholipids in the WB/WB + WS groups, respectively. The content of monounsaturated fatty acids(MUFA) was significantly higher, and the polyunsaturated fatty acids(PUFA) and saturated fatty acids(SFA) were significantly lower in the affected breasts. In the liver, 434 lipid molecules were identified, and 39/61 DA lipid molecules(6.7%/14.1%) were detected in the WB and WB + WS groups, respectively. In the serum, a total of 529 lipid molecules were identified and 4/44 DA lipid molecules(0.8%/8.3%) were detected in WB and WB + WS group, respectively. Compared to controls, the content of MUFAs in the serum and breast of the WB + WS group were both significantly increased, and the content of SFAs in two tissues were both significantly decreased. Only five lipid molecules were consistently increased in both liver and serum in WB + WS ***: We have found for the first time that the dominant lipid profile alterations occurred in the affected breast muscle. The relative abundance of 40.2% of lipid molecules were changed and is characteri

关键词： Broiler chicken Lipid profle Liver Serum Wooden breast

Two Bisligand-Coordinated Luminescent Zn(Ⅱ)-Coordination Polymers for Sensing of Ions and Pesticides in Aqueous Solutions

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Chinese Journal of Structural Chemistry 2022年第9期41卷 87-93页

作者： zhao-di Zhou Zi-Long Xu Dan Wang Lin-Fang Jia Han-Qing zhao Bao-Yi Yu Chong-Chen Wang Key Laboratory of Urban Agriculture(North China) Ministry of AgricultureCollege of Bioscience and Resources EnvironmentBejing University of AgricultureBejing102206China Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation Bejing University of Civil Engineering and ArchitectureBeijing 100044China

Two coordination polymers(CPs) [Zn(PTA)(DTP)(HO)]·(DMF)(CP-1) and [Zn(BTC)(DTP)]·(CHCN)·(HO)(CP-2) with one-and two-dimensional architectures were synthesized from Zn(Ⅱ) ion and different organic linkers like terephthalic acid(HPTA), benzene-1,3,5-tricarboxylic acid(HBTC), and 3,5-di(1,2,4-triazol-1-yl) pyridine(DTP). The fluorescent sensing experiments showed that the two CPs displayed effective, sensitive, and selective abilities towards Feand CrO. For sensing the pesticides, CP-1 outperforms in sensing of metamitron(MMT) and CP-2 is ultrasensitive towards imidacloprid(IMI). The possible mechanisms involved in the quenching of the fluorescence intensity include the inner filter effect(IFE) and the fluorescence resonance energy transfer(FRET) effect.

关键词： coordination polymer fluorescence sensing heavy metal ions pesticides X-ray crystallography

The Minor Precipitation at the Final Stage of U720Li Solidification

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Acta Metallurgica Sinica(English Letters) 2016年第6期29卷 518-526页

作者： Guang-di zhao Lian-Xu Yu Feng Qi Fang Liu Wen-Ru Sun Zhuang-Qi Hu Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

The minor precipitations caused by B and Zr which are the normal constituents of U720 Li alloy have been studied by analyzing the solidification process and the composition evolution. The present study aims to supply the elementary information about the existing form of B and Zr in the as-cast microstructure, which is helpful for the subsequent processing, such as homogenization treatment. The M_3B_2 and Ni_5Zr phases were observed in the U720 Li alloy in as-cast state, which were usually accompanying with each other together with g-Ni_3 Ti phase at the edge of eutectic（γ＋γ＇）. Combining the DTA analysis and heating and quenching tests, the solidification sequence was determined to be the following： c matrix, eutectic（γ＋γ＇）, g-Ni_3Ti, M_3B_2 and Ni_5Zr. The in situ composition analysis by EDS and EPMA revealed that the precipitation and microstructure were governed by the composition evolution in the liquids. The solidification of c matrix increased the Ti concentration in the residual liquids and resulted in the eutectic（γ＋γ＇） formation; the（γ＋γ＇） formation increased the Ti/Al radio in the liquids and the g-Ni_3Ti was formed in front of the eutectic（γ＋γ＇）; the g-Ni_3Ti precipitation consumed up Al and Ti and increased the concentration of B, Mo and Cr, and M_3B_2 boride is formed;the previous precipitation of the phases consumed up most of the elements other than Ni and Zr, and Ni_5Zr is formed finally. The melting points are in the ranges of 1130–1140 °C for Ni_5Zr phase, 1180–1190 °C for M_3B_2 boride and1190–1200 °C for g-Ni_3Ti phase.

关键词： Superalloy U720Li Solidification M3B2 boride Ni5Zr phase