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A　NEW　DITERPENOID　FROM　COLEUS　SCUTELLARIOIDES

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Chinese Chemical Letters 1996年第5期7卷 441-442页

作者： Mu, q Zhang, HJ Li, CM sun, HD ACAD SINICA KUNMING INST BOTLAB PHYTOCHEMKUNMING 650204PEOPLES R CHINA

Abstract: From the herbs of Coleus sculellarioides, a new diterpenoid was isolated and identified as 2-(2'ξ-methoxypropy)-3-hydroxy-5,7,8-trimethylphenanthrene-1,4--dione,named as scutequinone(1).

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Oxygen and Nitrogen Effects on MC Carbide in K465 Nickel-Base Superalloy

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稀有金属材料与工程 2009年第A03期38卷 13-16页

作者： Wang L N Zheng q.sun X F Guan H R Hu Z q Institute of Metals Research Chinese Academy of Sciences Shenyang 110015 China

Effects of oxygen and nitrogen on MC carbide in nickel-base superalloy K465 were investigated, because neither of the two gas elements was found to decide MC carbide morphology monotonically. The morphology of MC carbide under alloy solidified in conventional investment casting condition was observed to transform from script-type to block-type with the total oxygen and nitrogen content (gas content) in samples rising up from 1.2×10-6 mol/g to 2.6×10-6 mol/g. The area fraction and composition of the MC carbide also varied with increase of gas content. However, the morphology of MC carbide kept to be script-type even when gas content was up to 3.4×10-6 mol/g in samples solidified with a much higher cooling rate. These results indicate that effects of gas content on formation of MC carbide can be observed in specimens solidified with low cooling rate, but such changes in MC carbide cannot be found when the cooling rate is high.

关键词：氧碳化物氮含量物理性能碳化物

Shennan Road and the modernization of Shenzhen architecture

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Frontiers of Architectural Research 2020年第2期9卷 437-449页

作者： Cong sun Charlie q.L.Xue Department of Architecture and Civil Engineering City University of Hong KongHong KongChina

Shenzhen exemplifies the rapid development of urban planning and construction in *** the last 40 years,many representative urban spaces and buildings have been built on Shennan Road,the city’s main eastewest thoroughfare,which has witnessed the formation of a multicenter structural layout and the miraculous expansion of the *** iconic buildings were designed by Hong Kong or foreign *** continuous development along Shennan Road not only symbolizes the fruits of the reform and opening up policies of Shenzhen and even China,but also reflects the modern architectural history in *** study uses historical research methods to review the changes in the urban fabric and the design trends,as seen in representative buildings along Shennan Road in different *** addition to the transition path of the city center,the unique role of streets and buildings in the development of the urban structure is analyzed,and other urban functions and symbolic meanings are *** work contributes to the history and theory of the modernization of contemporary Chinese architecture.

关键词： Shenzhen architecture Shennan road Contemporary Chinese architecture Foreign design Rapid urbanization

Simulation study on the effect of pre-evacuation time and exit width on evacuation

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Chinese Science Bulletin 2006年第11期51卷 1381-1388页

作者： CHU Guanquan sun Jinhua WANG q ingsong CHEN Sining State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China

Occupant pre-evacuation time is often oversimplified into an explicit value in evacuation calculation. In fact, it is not an explicit value but a random variable following some kind of probability distribution. In order to analyze the importance of pre-evacuation time in evacuation calculation, Grid- Flow evacuation model is utilized to study the effect of pre-evacuation time on evacuation under different occupant densities and exit widths in a single room scenario. The evacuation time calculated by using normal pre-evacuation distribution is compared with that calculated by explicit pre-evacuation time. Two faults are presented when pre-evacuation time is considered as an explicit value. The theory of con- gestion and queue is presented to analyze the cal- culation results. Moreover, this paper also presents probability distribution of the total evacuation time when the pre-evacuation time follows normal distri- bution. The results show that the evacuation time is dominated by pre-evacuation time and hardly de- pendent on occupant density when the mean pre- evacuation time is long. For long mean pre-evacua- tion time, low occupant density or wide exit, when pre-evacuation time follows normal distribution, the total evacuation time also follows normal distribution.

关键词：火灾预疏散时间正态分布出口宽度居住密度模拟研究

Effect of Solid/Liquid Interface Morphology on Microstructure and Segregation of DSX40M Superalloy

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Journal of Materials Science & Technology 1995年第1期11卷 56-60页

作者： sun, LL WU, q ZHANG, ZY HU, ZG

The effect of solid/liquid interface morphologies on the microstructure and segregation of a new type superalloy, DSX40M, was studied. It has been found that the primary arm spacing presents maximum value as the solid/liquid interface shape transforms from cellular to cellular-dendritic. As the alloy solidifies with a coarse dendritic interface, the solute segregation degree and the average size of the carbide reach the maximum values because of the widest mushy zone. A Zr-rich phase forms at this range. Within the solidification rate range of dendritic interface, the primary dendritic arm spacing and solute segregation decrease with the increasing of solidification rate and the Zr-rich phase disappears. It should be indicated that the change of the solid/liquid interface does not vary the carbide type, but greatly affects the average size of the carbides. The quantitative results of the carbide size change in this alloy system with different solid/liquid interfaces is presented.

关键词： Effect of Solid/Liquid Interface Morphology on Microstructure and Segregation of DSX40M Superalloy

Synthesis and Room Temperature Ferromagnetism of Flower-shaped Mn Doped ZnO Nanostructures

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Journal of Materials Science & Technology 2011年第6期27卷 513-517页

作者： Y.q. Chang P.W. Wang R.H. Tang q.L. sun Y. Long School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Physics National Key Laboratory of Mesoscopic Physics Peking University Beijing 100871 China

Large-scale flower-shaped Mn doped ZnO nanostructures have been grown on silicon substrates by simple thermal evaporation at atmospheric *** flower-shaped nanostructure makes up of many nanorods,which are rooted in one *** of X-ray diffraction,high-resolution transmission electron microscopy and Raman spectra results reveal that the products are of single phase with wurtzite *** mapping results show that no impurity clusters exist in the doped *** photoluminescence spectra demonstrate that many oxygen vacancies exist in the doped materials,and the crystal quality is improved and the content of oxygen vacancies is decreased by annealing *** flower-shaped Mn doped ZnO nanostructures exhibit ferromagnetic ordering above room temperature,and its magnetization is decreased by the annealing treatment,which indicates that the magnetic behavior of the doped materials may be related to the interaction between Mn doping and the oxygen vacancies.

关键词： Mn doped ZnO nanomaterials Ferromagnetism Annealing treatment Chemical vapor deposition

Application of lung microphysiological systems to COVID-19 modeling and drug discovery:a review

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Bio-Design and Manufacturing 2021年第4期4卷 757-775页

作者： Argus M.sun Tyler Hoffman Bao q.Luu Nureddin Ashammakhi Song Li Department of Bioengineering Samueli School of EngineeringUniversity of California-Los Angeles420 Westwood Plaza 5121 Engineering V University of CaliforniaLos AngelesCA 90095-1600USA UC San Diego Healthcare UCSDLa JollaCA 92037USA Pulmonary Diseases and Critical Care Scripps Green HospitalScripps HealthLa JollaCA 92037USA Department of Biomedical Engineering College of EngineeringMichigan State UniversityEast LansingMI 48824USA Department of Medicine David Geffen School of MedicineUCLALos AngelesCA 90095USA

There is a pressing need for effective therapeutics for coronavirus disease 2019(COVID-19),the respiratory disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** process of drug development is a costly and meticulously paced process,where progress is often hindered by the failure of initially promising *** aid this chal-lenge,in vitro human microphysiological systems need to be refined and adapted for mechanistic studies and drug screening,thereby saving valuable time and resources during a pandemic *** SARS-CoV-2 virus attacks the lung,an organ where the unique three-dimensional(3D)structure of its functional units is critical for proper respiratory *** in vitro lung models essentially recapitulate the distinct tissue structure and the dynamic mechanical and biological interactions between different cell *** model systems include Transwell,organoid and organ-on-a-chip or microphysiological systems(MPSs).We review models that have direct relevance toward modeling the pathology of COVID-19,including the processes of inflammation,edema,coagulation,as well as lung immune *** also consider the practical issues that may influence the design and fabrication of *** role of lung MPS is addressed in the context of multi-organ models,and it is discussed how high-throughput screening and artificial intelligence can be integrated with lung MPS to accelerate drug development for COVID-19 and other infectious diseases.

关键词： Bioengineering Microfluidics COVID-19 Organ-on-a-chip Lung Microvascular networks Drug development

Analysis of extreme ultraviolet spectral profiles of laser-produced Cr plasmas

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Chinese Physics B 2019年第7期28卷 319-323页

作者： L Wu M G Su q Min S q Cao S q He D X sun C Z Dong Key Laboratory of Atomic and Molecular Physics & Functional Material of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal University

Radiation from laser-produced plasmas was examined as a potential wavelength calibration source for spectrographs in the extreme ultraviolet(EUV) ***, the EUV emission of chromium(Cr) plasmas was acquired via spatiotemporally resolved emission *** the aid of Cowan and flexible atomic code(FAC) structure calculations,and a comparative analysis with the simulated spectra, emission peaks in the 6.5–15.0 nm range were identified as 3 p–4 d, 5 d and 3 p–4 s transition lines from Cr5+–Cr10+ions.A normalized Boltzmann distribution among the excited states and a steady-state collisional-radiative model were assumed for the spectral simulations, and used to estimate the electron temperature and density in the *** results indicate that several relatively isolated emission lines of highly charged ions would be useful for EUV wavelength calibration.

关键词： laser-produced plasmas highly charged ions extreme ultraviolet wavelength calibration

FORMATION OF GRADIENT COATING OF Fe-BASED ALLOY WITH RARE EARTHS BY PLASMA SURFACING

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 713-718页

作者： L.J.Shang A.q.sun J.F.Chen C.M.Zhang q.K.Cai CollegeofMaterialsScienceandEngineering ShenyangPolytechnicUniversityShenyang110023China SchoolofMaterialsandMetallurgy NortheasternUniversityShenyang110004China

A gradient coating of Fe-based alloy was manufactured with rare earths (RE) by plasma surfacing on q235 steel substrate. The coatings were studied by using X-ray diffraction(XRD), scanning electron microscope(SEM), differential thermal analyzer(DTA), and electron probe micro-analyzer (EPMA). The results show that the phases of the two kinds of coatings(with and without RE) both include α-Fe, Fe7C3, Fe3C, Cr2B, Fe2B and FeB. The microstructure of F314 coating is mainly hypereutectic, the pro-phases Cr7C3 and Cr2B are loose, crassi, spiculate and contain microcracks. The brittleness of the coating is high, and the average hardness is 787 HV. When 0.8wt% RE was added into the F314 alloy, the microstructure varied from hypoeutectic to hypereutectic continuously, The hardness appears as gradient distribution with the highest value of 773 HV, meanwhile, the brittleness decreases significantly. The formation of gradient structure depends on the fallowing factors: (i) the conversion of RE. The addition of RE lowers the elements point and Fe-C eutectic temperature, thus the base metal melting acutely. (ii) the heating of plasma arc. Graded temperature results in directional solidification, thus the gradient structure forms easily. The main reasons for the hardness decrease with RE addition in the alloy are the ratio of hard phase lowering and the hardness of the hard phase decreasing.

关键词： rare earth plasma surfacing Fe-base alloy microstructure graded coating