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Radical recombination in a hydrocarbon-fueled scramjet nozzle

Chinese Journal of Aeronautics 2014年第6期27卷 1413-1420页

作者： Zhang Xiaoyuan Qin Lizi Chen Hong He xuzhao Liu Yu School of Astronautics Beihang University State Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Science China Aerodynamic Research and Develop Center

To reveal the radical recombination process in the scramjet nozzle flow and study the effects of various factors of the recombination, weighted essentially non-oscillatory（WENO）schemes are applied to solve the decoupled two-dimensional Euler equations with chemical reactions to simulate the hydrocarbon-fueled scramjet nozzle flow. The accuracy of the numerical method is verified with the measurements obtained by a shock tunnel experiment. The overall model length is nearly 0.5 m, with inlet static temperatures ranging from 2000 K to 3000 K, inlet static pressures ranging from 75 k Pa to 175 k Pa, and inlet Mach numbers of 2.0 ± 0.4 are *** fraction Damkohler number is defined as functions of static temperature and pressure to analyze the radical recombination progresses. Preliminary results indicate that the energy releasing process depends on different chemical reaction processes and species group contributions. In hydrocarbon-fueled scramjet nozzle flow, reactions with H have the greatest contribution during the chemical equilibrium shift. The contrast and analysis of the simulation results show that the radical recombination processes influenced by inflow conditions and nozzle scales are consistent with Damkohler numbers and potential dissociation energy release. The increase of inlet static temperature improves both of them, thus making the chemical non-equilibrium effects on the nozzle performance more significant. While the increase of inlet static pressure improves the former one and reduces the latter, it exerts little influence on the chemical non-equilibrium effects.

关键词： Chemical reactions Nozzles Performance calculation Radical Recombination

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Sediment storage and morphology of the Yalu Tsangpo valley due to uneven uplift of the Himalaya

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Science China Earth Sciences 2015年第8期58卷 1440-1445页

作者： WANG ZhaoYin YU Guo An WANG xuzhao Charles S. MELCHING LIU Le State Key Laboratory of Hydro-Science and Engineering Tsinghua University Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Beijing Institute of Geology for Mineral Resources Environmental Consultant

The fluvial process of the Yalu Tsangpo River occurs concurrently with the uplift of the Qinghai-Tibet ***,the river exhibits unique features in morphology and sediment *** investigations were performed from 2009–2011and the depth of the interface between the sediment deposits and bed rock was detected with an electromagnetic imaging system(EH4)at 29 cross *** deposits were sampled along the Yalu Tsangpo valley from Xietongmen to the Yalu Tsangpo *** results show that a huge amount of sediment has been deposited in four wide valley sections because the uplift rate in these sections was lower than that in the downstream gorge sections over the past million *** 518 billion m3of gravel and sand have been stored in the high mountain river valleys,which has changed the V-shaped mountain river valley into a U-shaped wide river valley in the four *** the sections with high uplift rates the river bed is incised and has formed gorges and the Yalu Tsangpo Canyon.

关键词： Yalu Tsangpo River sediment deposits uneven uplift himalaya wide valley

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Characterization of Ethylene Receptors and Their Interactions with GmTPR-A Novel Tetratricopeptide Repeat Protein (TPR) in Soybean (Glycine max L.)

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Journal of Integrative Agriculture 2013年第4期12卷 571-581页

作者： NIUYan yan CHENMing xuzhao shi LILian cheng CHENXue ping MAYOU zhi DepartmentofChemistry UniversityofScienceandTechnologyofChina.Hefei230026.户R.China TheNationalKeyFacilityfo CropGeneticResourcesandGeneticImprovementInstituteofCropSciencesChineseAcademyofAgriculturalSciencesBeijing』00081PR.China

Ethylene receptors play important roles not only in regulation of growth and development but also in response to environmental stimuli of plants. However, there are few reports on ethylene receptors in soybean. In this article, putative ethylene receptors of soybean were searched from soybean genomic database （http：//***/***） and analyzed. The ethylene receptor gene family in soybean comprising eight members, designated as GmERSI-1, GmERS1-2, GmETRI-1, GmETR1-2, GmETR2-1, GmETR2-2, GmEIN4-1, and GmEIN4-2 corresponding with their homologous genes in drabidopsis, were isolated and analyzed. Phylogenetic analysis indicated that the eight soybean ethylene receptors （SERs） were in two subfamilies and further divided into four groups, viz., groups I （GmERSI-1 and GmERS1-2）, 1I （GmETRI-1 and GmETR1-2）, VI （GmETR2-I and GmETR2-2）, and VII （GmEIN4-1 and GmEIN4-2）. Protein structure of the members in groups I and II from subfamily I were more conserved than the members in other two groups from subfamily II. Expression patterns of the SERs were compared with the homologous genes in Arabidopsis. The results demonstrated that expression patterns of the SERs differed from Arabidopsis members in the same group, suggesting that SERs are involved in different signal pathways compared to ethylene receptors in drabidopsis. Promoter analysis showed that the sequences of the members in each group were different from each other, and some specific binding elements of transcription factors detected in promoter sequences might explain the differences between the members in the same group. A novel soybean TPR protein （tetratricopeptide repeat protein）, GmTPR, was identified to interact with GmETRI-1, apparently an important ethylene receptor in ethylene signaling pathway in soybean. This suggested that GmTPR might be a novel downstream component of the ethylene signaling pathway.

关键词： soybean Arabidopsis ethylene receptor TPR protein

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Antifouling Potential of Bacteria Isolated from a Marine Biofilm

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Journal of Ocean University of China 2014年第5期13卷 799-804页

作者： GAO Min WANG Ke SU Rongguo LI xuzhao LU Wei Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of China Marine Chemical Research Institute

Marine microorganisms are a new source of natural antifouling compounds. In this study, two bacterial strains, Kytococcus sedentarius QDG-B506 and Bacillus cereus QDG-B509, were isolated from a marine biofilm and identified. The bacteria fermentation broth could exert inhibitory effects on the growth of Skeletonema costatum and barnacle larvae. A procedure was employed to extract and identify the antifouling compounds. Firstly, a toxicity test was conducted by graduated pH and liquid-liquid extraction to determine the optimal extraction conditions. The best extraction conditions were found to be pH 2 and 100% petroleum ether. The EC50 value of the crude extract of K. sedentarius against the test microalgae was 236.7 ± 14.08 μg mL-1, and that of B. cereus was 290.6 ± 27.11 μg mL-1. Secondly, HLB SPE columns were used to purify the two crude extracts. After purification, the antifouling activities of the two extracts significantly increased: the EC50 of the K. sedentarius extract against the test microalgae was 86.4 ± 3.71 μg mL-1, and that of B. cereus was 92.6 ± 1.47 μg mL-1. These results suggest that the metabolites produced by the two bacterial strains are with high antifouling activities and they should be fatty acid compounds. Lastly, GC-MS was used for the structural elucidation of the compounds. The results show that the antifouling compounds produced by the two bacterial strains are myristic, palmitic and octadecanoic acids.

关键词： marine biofilm bacteria antifouling activity fatty acids

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Antialgal and Antilarval Activities of Bioactive Compounds Extracted from the Marine Dinoflagellate Amphidinium carterae

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Journal of Ocean University of China 2016年第6期15卷 1014-1020页

作者： KONG Xianyu HAN Xiurong GAO Min SU Rongguo WANG Ke LI xuzhao LU Wei Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of ChinaQingdao 266100 P. R. China Marine Chemical Research Institute Qingdao 266071 P. R. China

Abstract With the global ban on the application of organotin-based marine coatings by the International Maritime Organization, the development of environmentally friendly, low-toxic and nontoxic antifouling compounds for marine industries has become an urgent need. Marine microorganisms have been considered as a potential source of natural antifoulants. In this study, the antifouling potential of marine dinoflagellate Amphidinium carterae, the toxic and red-tide microalgae, was investigated. We performed a series of operations to extract the bioactive substances from Amphidinium carterae and tested their antialgal and antilarval activities. The crude extract of Amphidinium carterae showed significant antialgal activity and the ECs0 value against Skeletonema costatum was 55.4 ~tg mL-1. After purification, the isolated bioactive substances （the organic extract C） exhibited much higher antialgal and antilar- val activities with ECso of 12.9μgmL-1 against Skeletonema costatum and LC50 of 15.1 μmL-1 against Amphibalanus amphitrite larvae. Subsequently, IR, Q-TOFMS, and GC-MS were utilized for the structural elucidation of the bioactive compounds, and a series of unsaturated and saturated 16- to 22-carbon fatty acids were detected. The data suggested the bioactive compounds isolated from Amphidinium carterae exhibited a significant inhibiting effect against the diatom Skeletonema costatum and Amphibalanus amphi- trite larvae, and could be substitutes for persistent, toxic antifouling compounds.

关键词： marine dinoflagellate bioactive compounds antialgal activity antilarval activity antifouling

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Highly efficient generation of blastocyst-like structures from spliceosomes-repressed mouse totipotent blastomere-like cells

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Science China(Life Sciences) 2023年第3期66卷 423-435页

作者： Pengfei Zhang xuzhao Zhai Boyan Huang Shu Sun Wen Jing Wang Man Zhang GMU-GIBH Joint School of Life Sciences The Guangdong-Hong Kong-Macao Joint Laboratory for Cell Fate Regulation and DiseasesThe Fifth Affiliated Hospital of Guangzhou Medical UniversityGuangzhou LaboratoryGuangzhou Medical UniversityGuangzhou 510005China Center for Cell Lineage and Atlas(CCLA) Bioland LaboratoryGuangzhou Regenerative Medicine and Health Guangdong LaboratoryGuangzhou 510005China

Mammalian embryogenesis begins with a totipotent ***-like structures can be captured by aggregated cells with extended pluripotent properties in a three-dimensional(3D)culture ***,the efficiency of generating blastoids is low,and it remains unclear whether other reported totipotent-like stem cells retain a similar *** this study,we demonstrated that spliceosomal repression-induced totipotent blastomere-like cells(TBLCs)form blastocyst-like structures within around 80%of all *** addition,we generated blastoids initiating from a single ***-blastoids express specific markers of constituent cell lineages of a blastocyst and resemble blastocyst in cell-lineage ***,singlecell RNA sequencing revealed that TBLC-blastoids share a similar transcriptional profile to natural embryos,albeit composed of fewer primitive endoderm-like ***,TBLC-blastoids can develop beyond the implantation stage in vitro and induce decidualization in *** summary,our findings provided an alternative cell type to efficiently generate blastoids for the study of early mouse embryogenesis.

关键词： blastoids TBLCs early embryogenesis totipotent

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Co-enhancement of thermal conduction and radiation through morphologies controlling of graphene functional layer for chip thermal management

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Nano Research 2024年第10期17卷 8885-8892页

作者： Shuting Cheng Kun Wang Shichen Xu Yi Cheng Ruojuan Liu Kewen Huang Hao Yuan Wenjuan Li Yuyao yang Fushun Liang Fan yang Kangyi Zheng Zhiwei Liang Ce Tu Mengxiong Liu Xiaomin yang Jingnan Wang xuzhao Gai Yuejie Zhao Xiaobai Wang Yue Qi Zhongfan Liu State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing 102249China Centre for Nanochemistry Beijing Science and Engineering Centre for NanocarbonsBeijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Beijing Graphene Institute(BGI) Beijing 100095China College of Energy Soochow Institute for Energy and Materials Innovations(SIEMIS)Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySuzhou 215006China Department of Chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China

With the continuous advancements in electronics towards downsizing and integration,efficient thermal dissipation from chips has emerged as a critical factor affecting their lifespan and operational *** fan-less chip cooling system has two critical interfaces for thermal transport,which are the contact interface between the base and the chip dominated by thermal conduction,and the surface of the fins dominated by thermal *** different thermal transfer modes of these two critical interfaces pose different requirements for thermal management *** the study,a novel approach was proposed by developing graphene thermal transport functional material whose morphology could be intentionally designed via reformed plasmaenhanced chemical vapor deposition(PECVD)methods to meet the diverse requirements of heat transfer ***,graphene with multilevel branching structure of vertical graphene(BVG)was fabricated through the hydrogenassisted PECVD(H_(2)-PECVD)strategy,which contributed a high emissivity of~*** was deposited on the fins’surface and functioned as the radiation enhanced layer to facilitate the rapid radiation of heat from the heat sinks into the surrounding ***,the well-oriented vertical graphene(OVG)was successfully prepared through the vertical electric field-assisted PECVD process(EF-PECVD),which showed a high directional thermal conductivity of~53.5 W·m^(-1)·K^(-1).OVG was deposited on the contact interface and functioned as the thermal conduction enhanced layer,allowing for the quick transmission of heat from the chip to the heat *** this design concept,the two critical interfaces in the chip cooling system can be jointly enhanced,resulting in a remarkable cooling efficiency enhancement of~30.7%,demonstrating that this novel material possessed enormous potential for enhancing the performance of cooling ***,this research not only provided new design concepts for the cooling system

关键词： chip thermal management thermal conduction thermal radiation graphene morphology control

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Slope Debris Flows in the Wenchuan Earthquake Area

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Journal of Mountain Science 2010年第3期7卷 226-233页

作者： LI Yanfu WANG Zhaoyin SHI Wenjing WANG xuzhao State Key Laboratory of Hydroscienee and Engineering Tsinghua University Beijing 100084 China Beijing Institute of Geology for Mineral Resources Beijing 100012 China

Avalanches and landslides,induced by the Wenchuan Earthquake on May 12,2008,resulted in a lot of disaggregated,solid material on slopes that could be readily mobilized as source material for debris *** triggered numerous slope debris flows with great damage to highways and rivers over the subsequent two *** debris flows(as opposed to channelized debris flows) are defined as phenomena in which high-concentration mixtures of debris and water flow down slopes for short distances to highways and river *** on field investigations and measurements of 19 slope debris flows,their main characteristics and potential mitigation strategies were *** rainfall intensity is the main triggering *** rainfall intensities for simultaneous occurrence of single,several and numerous slope debris flow events were 20 mm/day,30mm/day,and 90 mm/day,*** investigations also revealed that slope debris flows consist of high concentrations of cobbles,boulders and *** are two-phase debris *** liquid phase plays the role of lubrication instead of transporting *** particles collide with each other and consume a lot of *** velocities of slope debris flows are very low,and their transport distances are only several tens of *** debris flows may be controlled by construction of drainage systems and by reforestation.

关键词： Slope debris flow rainfall intensity Wenchuan Earthquake landslide avalanche

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WKPowerMeans多径簇识别算法

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天津大学学报（自然科学与工程技术版） 2014年第3期47卷 237-242页

作者：杨晋生吴旭曌天津大学电子信息工程学院天津300072

针对KPowerMeans聚类算法多径散射簇的估计过程复杂及聚类结果高度依赖随机初始簇中心的问题,提出了一种改进的多径簇识别算法——WKPowerMeans算法.首先利用小波变换的尖峰检测技术估计出多径散射簇的数目和初始簇中心的位置,然后以结... 详细信息

针对KPowerMeans聚类算法多径散射簇的估计过程复杂及聚类结果高度依赖随机初始簇中心的问题,提出了一种改进的多径簇识别算法——WKPowerMeans算法.首先利用小波变换的尖峰检测技术估计出多径散射簇的数目和初始簇中心的位置,然后以结合了多径功率加权的多径分量距离为准则进行多径簇聚类.仿真结果表明:与KPowerMeans算法相比,采用所提出的WKPowerMeans算法能得到更稳定、准确的聚类结果,而且具有较低的时间复杂度.

关键词：多径簇识别 KPowerMeans算法信息熵尖峰检测

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On the Fossil Pediastrum from the Gaoximage Section, Hunshandak Sandy Land and Its Ecological Significance Since 5 000 a BP

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Acta Botanica Sinica 2004年第10期46卷 1141-1148页

作者： xuzhao-Liang LIChun-Yu KONGZhao-Chen LaboratoryofSystematicandEvolutionaryBotany InstituteofBotanyTheChineseAcademyofSciencesBeijing100093China GraduateSchoolofTheChineseAcademyofSciences Beijing100039China

The fossil Pediastrum was investigated from the Gaoximage section ( 42°57′14″ N, 115°22′3″E, Air 1 253 m ) in the Hunshandak Sandy Land, Inner Mongolia (Nei Mongol) of China in order to gain a better understanding the changes of palaeovegetation, palaeoenvironment and palaeoclimite since 5000 aBP when the pollen-spore was studied. The results show that the fossil Pediastrum assemblage can be divided into three periods: Ⅰ. 5 000-3 500 a BP, the fossil Pediastrum occurred rarely. Based on this result it can be surmised that the lake might be fresh water with poor organics. Ⅱ. 3 500-1 500 a BP, the fossil Pediastrum likes volcanic emerged. It probably indicate moist conditions and the grasslands were developed during this time; and Ⅲ. 1 500-200 a BP, the fossil Pediastrum disappeared. It can show that the lake water become salty and shrunk, and the weather could become drier and drier. This result shows that Pediastrurn, a kind of facies fossil, happened simultaneously in the pollen-spore assemblage during the second period. Sometimes Pediastrurncan reach more than 60 per cent of the total spore pollen assemblage, indicating that Gaoximage lake was not only fresh water with abundant eutrophic materials but also occupied a large area during 3 500-1 500 a BP.

关键词：化石盘星藻属砂地荒漠化生态学中国内蒙古古植被

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