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Experimental investigation on unstart-restart hysteresis of a supersonic inlet during throat regulation

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Chinese Journal of Aeronautics 2023年第11期36卷 135-152页

作者： Yi JIN Huijun TAN Hao ZHANG Gaojie ZHENG shu sun Yue ZHANG Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace Times Feipeng Company Limited China Academy of Aerospace Electronics TechnologyKunshan 215000China

The hysteresis during the throat regulation process of a supersonic variable inlet is unconducive to ***,detailed experimental studies of such a hysteresis and its control are necessary.A throat variable supersonic inlet was designed at a shock-on-lip Mach number of 4.0 and an Internal Contraction Ratio(ICR)ranging over 1.21–***,a distributed bleed system was proposed to suppress the *** wind tunnel tests were conducted at Mach number *** throat regulation processes were recorded using a high-speed schlieren and dynamic pressure acquisition *** results indicate that the unstart and restart ICRs during the uncontrolled inlet’s throat regulation process were 1.95 and 1.48,respectively,demonstrating an unstart-restart *** typical flowfields were summarized during the uncontrolled inlet’s restart *** proposed bleed control increased the unstart and restart ICRs to 2.06 and 1.75,respectively,and the inlet realized the designed state as the ICR was further decreased to *** controlled inlet’s hysteresis loop was decreased compared to the uncontrolled ***,the mechanism of the hysteresis,dominated by the entrance separation-induced wave system,was *** mechanisms of the bleed control to broaden the unstart and restart boundaries and suppress the hysteresis were elucidated.

关键词： Supersonic inlet Unstart-restart hysteresis Bleed control Throat regulation process Wind tunnel test

To increase more than 10% in efficiency of perovskite solar cells by using nanoholes SnO_(2)

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Rare Metals 2021年第10期40卷 2778-2784页

作者： shu-Ren sun Xi-Xi Xie Guo-Gang Qin Li-Xin Xiao State Key Laboratory for Mesoscopic Physics and Department of Physics Peking UniversityBeijing 100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The perovskite solar cells have been intensively investigated these years due to their premium electrical and optical properties as well as huge potential for *** order to further increase the power conversion efficiency(PCE) of the thin film perovskite solar cells, light management should be taken into consideration. Herein, we apply a lithography method to transfer randomly distributed polystyrene(PS) nanospheres into the electron transporting SnO_(2) layer, by means of which, a nanoholes structure is formed. Finally, we get a nanostructured perovskite layer under low temperature(less than 150 ℃).The depth of SnO_(2) nanoholes is around 60 nm when the device is fabricated with 300-nm PS, and 150 nm in depth when 500-nm PS is used. The device gains PCE of 17.97%,which is 12.3% higher than that with planar electrontransporting SnO_(2) layer and 300-nm CH_(3)NH_(3)PbI_(3) *** findings provide an applicable method to improve the light absorption, which can not only make the absorbing layer of lead-based perovskite solar cells thinner to help decrease the content of lead, but also increase the PCE of non-lead perovskite devices.

关键词： Light trap Perovskite Solar cell Nanohole Nanosphere lithography

Synthesis of granulated Li_(1.33)Mn_(1.67)O_(4) via two antisolvent methods for lithium adsorption from gas-produced water

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Chinese Journal of Chemical Engineering 2024年第5期69卷 34-46页

作者： Jun Qiu Lu-Ri Bao Wei Guo Ying Yang shu-Ying sun National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China

Gas-produced water is an accompanying wastewater in the natural gas extraction process,and it is a potential liquid lithium resource that contains a considerable amount of *** study investigated the feasibility of using manganese-based ion sieves to adsorb and extract lithium from gas-produced *** we focused on the applicability of two different granulation methods,extrusion and droplet,in gas-produced water *** types of H_(1.33)Mn_(1.67)O_(4) particles were prepared by the extrusion method(EHMO)and the droplet method(DHMO).The porosity of DHMO was much higher than that of EHMO,and the adsorption performance of DHMO increased with the decrease of binder *** prepared with a binder concentration of 0.14 g·ml^(-1)exhibited the best adsorption performance in gas-produced water,and the Li^(+)adsorption capacity could reach 25.14 mg·g^(-1).In gas-produced water,the adsorption equilibrium of DHMO only took 9 h,and the adsorption process conformed to the Langmuir model and pseudo-second-order kinetic *** pore diffusion model(PDM)could well describe its adsorption ***,DHMO showed a great selectivity to Li^(+),and the selectivity order of DHMO in gas-produced water was Li^(+)>Ba^(2+)>>Mg^(2+),Ca^(2+),Sr^(2+)>>Na^(+)>>K^(+).After 20 cycles,the Li^(+)adsorption capacity was still higher than 17.30 mg·g^(-1),and the rate of manganese dissolution was less than 1%.

关键词： Gas-produced water Granulation Li_(1.33)Mn_(1.67)O_(4)

Antioxidation of Anthocyanins in Photosynthesis Under High Temperature Stress

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Journal of Integrative Plant Biology 2007年第9期49卷 1341-1351页

作者： Ling Shao Zhan shu shu-Lan sun Chang-Lian Peng Xiao-Jing Wang Zhi-Fang Lin College of Life Science Guangdong Provincial Key Laboratory of Biotechnology for Plant Development South China Normal University Guangzhou 510631 China Biology Department Zhao Qing University Zhaoqing 526061 China South China Botanical Garden the Chinese Academy of Sciences Guangzhou 510650 China

Chlorophyll fluorescence and antioxidative capability in detached leaves of the wild type Arabidopsis thaliana L. ecotype Landsberg erecta （Ler） and three mutants deficient in anthocyanins biosynthesis （tt3, tt4, and tt3tt4） were investigated during treatment with temperatures ranging 25-45 ℃. In comparison with the wild type, chlorophyll fluorescence parameters Fv/Fm, φps,, electron transport rate （ETR）, Fv/Fo and qP in three anthocyanin-deficient mutants showed a more rapidly decreasing rate when the temperature was over 35 ℃. Non-photochemical quenching （NPQ） in these mutants was almost completely lost at 44 ℃, whereas the content of heat stable protein dropped and the rate of the membrane leakage increased. Fo-temperature curves were obtained by monitoring Fo levels with gradually elevated temperatures from 22 ℃ to 72 ℃ at 0.5 ℃/min. The inflexion temperatures of Fo were 45.8 ℃ in Ler, 45.1℃ in tt3, 44.1℃ in tt4 and 42.3 ℃ in tt3tt4, respectively. The temperatures of maximal Fo in three mutants were 1.9-3.8℃ lower than the wild type plants. Meanwhile, three mutants had lower activities of superoxide dismutase （SOD） and ascorbate peroxidase （APX） and an inferior scavenging capability to DPPH （***） radical under heat stress, and in particular tt3tt4 had the lowest antioxidative potential. The results of the diaminobenzidine-H2O2 histochemical staining showed that H2O2 was accumulated in the leaf vein and mesophyll cells of mutants under treatment at 40 ℃, and it was significantly presented in leaf cells of tt3tt4. The sensitivity of Arabidopsis anthocyanins-deficient mutants to high temperatures has revealed that anthocyanins in normal plants might provide protection from high temperature injury, by enhancing its antioxidative capability under high temperature stress.

关键词： anthocyanins-deficient mutant antioxidative capability Arabidopsis thaliana chlorophyll fluorescence H2O2 histochemical localization high temperature stress.

Rb-Sr chronological characteristics of Jurassic granitoid gravels in north margin of Dabie block,Central China

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Chinese Science Bulletin 2001年第13期46卷 1126-1129页

作者： Li Zhong Li Renwei sun shu Zhang Wenhua Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Granitoid gravels are discovered from alluvial fan conglomerates, the base of Jurassic Fenghuangtai Formation (J22), in the north margin of Dabie block and the south part of the Hefei Basin. These granitoid gravels make up 5%-10% of all gravels by volume percent. For the four components, K-feldspar, biotite, amphibole and whole rock divided from two selected granitoid gravel samples, their Rb-Sr isotopes are measured, which gives two formation ages of granitoids: (428±20) Ma and (430±54) Ma, and means that the Early Paleozoic granitoid intrusive rocks once existed in the Dabie Mountain provenances of Jurassic. The granitoids occur in the tectonic setting of post-collision upliftaccording to lithogeochemical discriminant analysis.

关键词： Dabie block Hefei Basin granitoid gravels Rb-Sr isotope chronology depositional provenance.

Application of the Bayes’ theory to the failure rate evaluation of electrical apparatus

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 501-505页

作者： JIN Shao-hua LU Jian-guo WAN Yan-ping sun shu-guang Department of Mathematics Hebei University of Technology Tianjin 300130 China

The Weibull distribution has been widely used in reliability fields. A mixed Weibull distribution represents a popu- lation that consists of several Weibull subpopulations. In this paper, a new approach which combines the least-squares method with Bayes’ theorem, takes advantage of the parameter estimation for single Weibull distribution is developed to estimate the pa- rameters of each subpopulation. The estimates given by this paper also satisfy the maximum likelihood equation. The estimates of the failure rate of the mixed Weibull population are given. An actual test data is computed by using the proposed method. The Kolmogorov-Smirnov goodness-of-fit test turns out that the proposed method yields more accurate result.

关键词： Bayesian estimation Failure rate Least-squares method Maximum likelihood principle Mixed-Weibull distribution

Stability analysis of slope in strain-softening soils using local arc-length solution scheme

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Journal of Mountain Science 2017年第1期14卷 175-187页

作者： WANG Xiang-rong RONG Qi-guo sun shu-li WANG Hui College of Engineering Peking University Graduate School AICES RWTH Aachen University

Soils with strain-softening behavior — manifesting as a reduction of strength with increasing plastic strain — are commonly found in the natural environment. For slopes in these soils,a progressive failure mechanism can occur due to a reduction of strength with increasing strain. Finite element method based numerical approaches have been widely performed for simulating such failure mechanism,owning to their ability for tracing the formation and development of the localized shear strain. However,the reliability of the currently used approaches are often affected by poor convergence or significant mesh-dependency,and their applicability is limited by the use of complicated soil models. This paper aims to overcome these limitations by developing a finite element approach using a local arc-length controlled iterative algorithm as the solution strategy. In the proposed finite element approach,the soils are simulated with an elastoplastic constitutive model in conjunction with the Mohr-Coulomb yield function. The strain-softening behavior is represented by a piece-wise linearrelationship between the Mohr-Coulomb strength parameters and the deviatoric plastic strain. To assess the reliability of the proposed finite element approach,comparisons of the numerical solutions obtained by different finite element methods and meshes with various qualities are presented. Moreover,a landslide triggered by excavation in a real expressway construction project is analyzed by the presented finite element approach to demonstrate its applicability for practical engineering problems.

关键词： Strain-softening Progressive failure Slope stability Local arc-length scheme Numerical simulation

Mass Spectrometric Studies on Metal-hexafluorobenzene Anionic Complexes(M=Ag, Au, Pd, Pt, Pb and Bi)

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Chemical Research in Chinese Universities 2009年第2期25卷 228-233页

作者： sun Zhang sun shu-tao LIU Hong-tao ZHU Qi-he GAO Zhen TANG Zi-chao Beijing National Laboratory for Molecular Sciences（BNLMS） State Key Laboratory of Molecular Reaction Dynamics Center of Molecular Science Institute of Chemistry Chinese Academy of Sciences Beo＇ing 100080 P. R. China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P R. China

The anionic products from the reactions between metal（M=Ag, Au, Pd, Pt, Pb and Bi） vapour produced by laser ablation and hexafluorobenzene seeded in carrier gas（Ar） were studied by means of a homemade reflectron time-of-flight mass spectrometry（RTOF-MS）. Experimental results show that the dominant products were [MmC6F6]^- complexes for the reactions ofAg, Au, Pd and Pt with C6F6, while the dominant products were [MmC6F5]^- complexes for the reactions of Pb and Bi with C6F6. The formation mechanisms of the products, including the adsorption of metal cluster anions on hexafluorobenzene and the C--F cleavage induced by metal cluster anions, were discussed.

关键词： Time-of-flight mass spectrometer Metal cluster Anionic complex Reaction mechanism

Analysis of Single Nucleotide Polymorphism in Human Paraoxonase 1 Gene(Q192R) with Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry

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Chemical Research in Chinese Universities 2006年第3期22卷 394-396页

作者： sun Ya-dong sun shu-chen WANG Zhi YANG Yang ZHANG Jin Key Laboratory for Molecular Enzymology and Engineering of Educational Ministry Jilin University Changchtm 130021 P. R. China People＇s Hospital of Jilin Province Changchun 130021 P. R. China

Introduction Single nucleotide polymorphisms （SNPs） are the most abundant DNA markers in the human genome occurring at a frequency of one in every 500--1000 nucleotides. A variety of methods have been used for the analysis of single nucleotide polymorphisms, including restriction fragment length polymorphism （RFLP）, direct sequencing by using laser-induced fluorescence detectionTM, fluorescence energy transfer, MALDI-TOF MS combined with primer extension or invasive cleavage, and fluorescence polarization. During the past two decades, mass spectrometry has become a very popular tool in the analysis of biomolecules and is perfectly suited to the analysis of single nucleotide polymorphisms （SNPs） due to its speed, low cost, and accuracy. In this work, we used MALDI TOF mass spectrometry to detect the fragments of restriction endonuclease hydrolysis of PCR products flanking a SNP located at paraoxonase 1（Q192R）. Compared with electrophoresis, this method requires less time of analysis and possess a higher accuracy.

关键词： Single nucleotide polymorphism Human paraoxonase 1 gene Matrix-assisted laser desorption/ionizationtime-of-flight mass spectrometry