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Journal of Magnesium and Alloys 2023年第7期11卷 2541-2557页

作者： Fan Shi Jingmao Zhao Mohammad Tabish Jingbao Wang pu Liu Jiayu chang College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China

The addition of 2,5-pyridinedicarboxylic acid(2,5-PDCA)to the Mg-Al LDH coating,which was prepared by one-step hydrothermal synthesis,had extremely enhanced the corrosion protection of AZ31 Mg alloy,although the 2,5-PDCA could not be intercalated into the interlayer *** corrosion current density of 0.05 mol L^(−1)2,5-PDCA LDH containing LDH coating is 3.18 nA cm^(−2),reduced by two orders of magnitude compared to the LDH coating without inhibitor,and the corrosion inhibition efficiency of the coating is 98.05%.The coating formed on the surface of AZ31 was peeled off from the substrate by using a mechanical method and SEM observation of the cross-section showed that the coating consisted of three different *** innermost layer is a thick layer that consists of Mg(OH)_(2)and the intermediate layer is LDH,which is vertical to the substrate and the outmost layer is a thin but very dense deposit layer of LDH agglomerates with complexes of 2,5-PDCA and *** kind of sediment/LDH/Mg(OH)_(2)three-layer composite structure was accountable for the increase in the corrosion resistance of AZ31 Mg alloy.

关键词： Three-layer composite coating Hydrothermal synthesis 2,5-PDCA MgAl-LDHs Peeling

Promoted porous Co_3O_4-Al_2O_3 catalysts for ammonia decomposition

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Science China Chemistry 2018年第11期61卷 1389-1398页

作者： zhe-Shan Zhang Xin-pu Fu Wei-Wei Wang Zhao Jin Qi-Sheng Song Chun-Jiang Jia Key Laboratory for Colloid and Interface Chemistry Key Laboratory of Special Aggregated Materials School of Chemistry and Chemical Engineering Shandong University

Transition metal catalysts have been considerably used for NH3 decomposition because of the potential application in COx-free H2 generation for fuel cells. However, most transition metal catalysts prepared via traditional synthetic approaches performed the inferior stability due to the agglomeration of active components. Here, we adopted an efficient method, aerosol-assisted self- assembly approach （AASA）, to prepare the optimized cobalt-alumina （C0304-A1203） catalysts. The C0304-A1203 catalysts exhibited excellent catalytic performance in the NH3 decomposition reaction, which can reach 100% conversion at 600 ℃and maintain stable for 72 h at a gaseous hourly space velocity （GHSV） of 18000 cm3 gcat-1 h-1. The catalysts were characterized by various techniques including transmission electron microscope （TEM）, scanning electron microscope （SEM）, nitrogen sorption, temperature-programmed reduction by hydrogen （H2-TPR）, ex-situ/in-situ Raman and ex-situ/in-situ X-ray diffraction （XRD） to obtain the information about the structure and property of the catalysts. H2-TPR and in-situ XRD results show that there is strong interaction between the cobalt and alumina species, which influences the redox properties of the catalysts. It is found that even a low content of alumina （10 at%） is able to stabilize the catalysts due to the adequate dispersion and rational interaction between different components, which ensures the high activity and superior stability of the cobalt-alumina catalysts.

关键词： cobalt-alumina catalyst aerosol-assisted self-assembly approach ammonia decomposition anti-sintering redox prop-erties

Conductive Metal/Covalent Organic Frameworks for CO_(2) Electroreduction

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Chinese Journal of Structural Chemistry 2022年第5期41卷 1-14页

作者： chang-pu Wan Jun-Dong Yi Rong Cao Yuan-Biao Huang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China School of Chemistry and Materials Science Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)University of Science and Technology of ChinaHefei 230026China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

Porous crystalline metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)are promising platforms for electrocatalytic reduction of CO_(2)(CO_(2)RR)due to their large CO_(2)adsorption uptakes and periodically arranged single active ***,the applications in CO_(2)RR of the traditional MOFs and COFs are greatly limited by their low electron *** recent years,numerous types of MOFs and COFs with high intrinsic conductivity have been rationally designed and successfully constructed,and some of them have been applied in CO_(2)*** this review,the applications of conductive MOFs and COFs in CO_(2)RR have been *** conductive MOFs and COFs can be categorized according to the methods,in which the conductivity is enhanced,such as constructing fullyπ-conjugated backbones,donor-acceptor heterojunction,enhancing theπ-πstacking interactions between organic moieties and/or the introduction of guest molecules.

关键词： metal-organic frameworks covalent organic frameworks CO_(2)electroreduction reaction conductive frameworks

Anisotropic power spectrum and the observed low-l power in PLANCK CMB data

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Research in Astronomy and Astrophysics 2018年第3期18卷 47-56页

作者： zhe chang Pranati K.Rath Yu Sang Dong Zhao Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China University of Chinese Academy of Sciences Beijing 100049 China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China

In this work,we study a direction dependent power spectrum in anisotropic Finsler spacetime. We use this direction dependent power spectrum to address the low-l power observed in WMAP and PLANCK data. The angular power spectrum of the temperature fluctuations has a lower amplitude in comparison to the ΛCDM model in the multipole range l = 2-40. Our theoretical model gives a correction to the isotropic angular power spectrum Cl^TT ldue to the breaking of rotational invariance of the primordial power spectrum. We estimate best-fit model parameters along with the six ΛCDM cosmological parameters using the PLANCK likelihood code in Cosmo MC software. We find that this modified angular power spectrum fits the CMB temperature data in the multipole range l = 2-10 to a good extent but fails for the whole multipole range l = 2-40.

关键词： cosmic background radiation - large-scale structure of universe

The third-party regulation on food safety in China:A review

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Journal of Integrative Agriculture 2015年第11期14卷 2176-2188页

作者： ZHANG Man QIAO Hui WANG Xu pu Ming-zhe YU Zhi-jun zheNG Feng-tian School of Agricultural Economics and Rural Development Renmin University of China School of Continuing Education Renmin University of China

Stakeholders in the field of food safety management in China can be classified into three categories, government, food producers （farmers and enterprises）, and the third-party regulatory bodies. The third-party regulation has experienced rapid development in past twenty years, and recently received considerable attention from consumers and the central government. This paper provides a review about the development, problems and future trend of the third-party regulation on food safety in China. To be specific, five forms of the third-party regulation are assessed, including media exposure, the third-party certification, regulation by consumer associations, social movements promoted by non-governmental organiza- tions （NGOs）, and regulation by industry associations. The study concludes that media and consumer associations are the major players in the third-party regulation and are highly repudiated among customers. The food certification industry has developed rapidly, but is now facing crises of confidence among consumers because of its lack of self-regulation. NGOs and industry associations still remain in the early development stages of food safety management, and therefore, are of little importance in current regulatory bodies.

关键词： food safety China the third-party regulation media certification

The ultraviolet colour component enhances the attractiveness of red flowers of a bee-pollinated plant

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Journal of Plant Ecology 2020年第3期13卷 354-360页

作者： zhe Chen chang-Qiu Liu Hang Sun Yang Niu CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 100049China Center for Gardens and Horticultural Studies Guangxi Institute of BotanyChinese Academy of SciencesGuilin 541006GuangxiChina

Aims Bee-pollinated flowers are rarely red,presumably because bees(which lack red receptors)have difficulty detecting red *** the response of bees to red colour has been investigated in lab experiments,most stimuli have been pure red,while the subtle diversity of red as perceived by humans(human-red)has received very limited *** we test the hypothesis that ultraviolet(UV)reflected from human-red flowers enhances their attractiveness to bees,through increased chromatic *** Using Onosma confertum(Boraginaceae),a plant with UV-reflecting red flowers that are pollinated by bumblebees,we investigated the effects of UV reflection on pollinator responses by conducting phenotypic manipulation experiments in the *** preferences of flower-naïve bumblebees were also *** perception by bumblebees was estimated in terms of chromatic and achromatic contrast,based on two different colour perception *** Findings We found that both natural and flower-naïve bumblebees strongly preferred visiting UV-reflecting targets compared with UV-absorbing *** models show that the UV-reflecting flowers exhibit higher spectral purity and higher chromatic contrast against the foliage background,whereas they have similar achromatic contrast in terms of green receptor *** results indicate that the component of UV reflection increases chromatic contrast in ***,enhancing the visual attractiveness of these red flowers to *** further infer that the secondary reflectance might be a necessary component in human-red flowers that are primarily pollinated by animals without red receptors,such as bees.

关键词： bee pollination colour vision floral colour evolution pollination syndrome red flower UV reflection

Research on resonance parameters matching based on partitioned operation method of atmospheric pressure plasma reactor array

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Plasma Science and Technology 2019年第5期21卷 34-42页

作者： zhe YU Jialin ZHAO Rui LIU Huijuan CAO pu LIU Zhitao ZHANG College of Science Dalian Maritime UniversityDalian 116026People's Republic of China Institute of Marine Engineering Dalian Maritime UniversityDalian 116026People's Republic of China

Matching optimization of resonant parameters among the high power inverters,low power transformers and plasma reactors have significant effects on the performance and output of the reactor array when applying the partitioned operation *** this paper,the Matlab/Simulink electrical model was established based on the method of partitioned *** matching relation between resonant parameters is analyzed on the basis of experimental *** a consequence,transformer leakage inductance and working frequency are the important parameters influencing the operational efficiency of system,leakage inductance of transformer should be adjusted based on the equivalent capacitance of plasma reactor to realize the matching optimization of resonant parameters.

关键词： atmospheric pressure plasma reactor dielectric barrier discharge Matlab/Simulink resonance parameters partitioned operation method

Lake water storage change estimation and its linkage with terrestrial water storage change in the northeastern Tibetan Plateau

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Journal of Mountain Science 2021年第7期18卷 1737-1747页

作者： LI Ya-wei WANG Yu-zhe XU Min KANG Shi-chang Key Laboratory of Tibetan Environment changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100039China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China CAS Centre for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China

Tibetan Plateau(TP) lakes are important water resources,which are experiencing quick expansion in recent *** researches mainly focus on analyzing the relationship between terrestrial water storage(TWS) change and lake water storage(LWS) change in the total inner TP,it is still lack of researches about the spatial difference and the characteristic of sub-region in the inner *** this study,we estimated the area change of 34 lakes by using Landsat images in the northeastern TP during 1976–2013,and LWS change by using the Shuttle Radar Topography Mission(SRTM).The results suggested that LWS had shrunk from 1976 to 1994,and then expanded quickly until *** had a serious decrease by 13.6 Gt during 1976–1994,and then it increased quickly by 35.4 Gt during 1994–*** estimated TWS change,soil moisture change,and permafrost degradation based on the satellite data and related models during 2003–*** results indicated that their changing rates were 1.86 Gt/y,0.22 Gt/y,and –0.19 Gt/y,*** also calculated the change of groundwater based on the mass balance with a decreasing trend of –0.054 Gt/*** results suggested that the cause of TWS change was the increase of *** analyzed the cause of lake change according to water balance,and found that the primary cause of lake expansion was the increasing precipitation(80.7%),followed by glacier meltwater(10.3%) and permafrost degradation(9%).The spatial difference between LWS change and TWS change should be studied further,which is important to understand the driving mechanism of water resources change.

关键词： Lake expansion GRACE Water storage change Precipitation Glacier meltwater

Gravitational Collapse of a Spherical Star with Heat Flow as a Possible Energy Mechanism of Gamma-Ray Bursts

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Communications in Theoretical Physics 2008年第7期50卷 271-274页

作者： chang zhe GUAN Cheng-Bo HUANG Chao-Guang LI Xin Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China Department of Physics Weihai Branch of Shandong University Weihai 264209 China

We investigate the gravitational collapse of a spherically symmetric, inhomogeneous star, which is described by a perfect fluid with heat flow and satisfies the equation of state p = p/3 at its center. In the process of the gravitational collapse, the energy of the whole star is emitted into space. And the remaining spacetime is a Minkowski one without a remnant at the end of the process. For a star with a solar mass and solar radius, the total energy emitted is at the order of 10^54 erg, and the time-scale of the process is about 8 s. These are in the typical values for a gamma-ray burst. Thus, we suggest the gravitational collapse of a spherical star with heat flow as a possible energy mechanism of gamma-ray bursts.

关键词： gravitational collapse gamma-ray burst

Young thoracic vertebra diffuse idiopathic skeletal hyperostosis with Scheuermann disease:A case report

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World Journal of Clinical Cases 2023年第3期11卷 655-661页

作者： Wen-zheng Liu zheng-Qi chang zhe-Ming Bao The First Clinical Medical College Shandong University of Traditional Chinese MedicineJinan 250000Shandong ProvinceChina Department of Orthopedics 960th Hospital of PLAJinan 250031Shandong ProvinceChina

BACKGROUND Diffuse idiopathic skeletal hyperostosis(DISH)is a disorder characterised by the calcification and ossification of ligaments and *** is a frequent occurrence in elderly males,but rarely encountered in younger *** SUMMARY A 24-year-old male was admitted to the hospital due to low back pain accompanied with numbness in both lower limbs for 10 *** clinical examination and imaging tests,the patient was diagnosed with DISH with Scheuermann disease and thoracic spinal *** the operation and medical treatment,the patient had hypoesthesia of the skin below the xiphoid ***,a standard laminectomy was conducted using ultrasonic bone curette and internal fixation was ***,the patient was given corticosteroids,neurotrophic drugs,hyperbaric oxygen and electric *** a result of the treatment,the patient’s sensory level decreased to the navel level and there was no major change in the muscle strength of the lower *** follow-up,the patient’s skin sensation has returned to *** This case is a rare instance of DISH co-existing with Scheuermann’s disease in a young *** provides a valuable reference point for spine surgeons,as DISH is more commonly observed in middle-aged and elder adults.

关键词： Diffuse idiopathic skeletal hyperostosis Scheuermann disease Thoracic spinal stenosis Case report