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Development and application of flexible substrate sensors in instantaneous heat flux measurement

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Chinese Science Bulletin 2009年第8期54卷 1311-1316页

作者： XU duo GU JiaHua wu Song Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

A new type of sensor with the flexible substrate is *** is applicable in measuring instantaneous heat flux on the model surface in a hypersonic shock *** working principle,structure and manufacture process of the sensor are *** substrate thickness and the dynamic response parameter of the sensor are *** this sensor was successfully used in measuring the instantaneous heat flux on the surface of a flat plate in a detonation-driven shock tunnel,it may be effective in measuring instantaneous heat flux on the model surface.

关键词：柔性衬底传感器热通量测量瞬时应用激波风洞高超声速

Holocene climate changes and paleoecology on the Tibetan Plateau:recent advances

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Frontiers of Earth Science 2023年第4期17卷 899-904页

作者： Juzhi HOU Xianyong CAO duo wu Mingda WANG Group of Alpine Paleoecology and Human Adaptation State Key Laboratory of Tibetan Earth SystemResources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China MOE Key Laboratory of Western China’s Environmental Systems College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China School of Geographical Sciences Liaoning Normal UniversityDalian 116029China

*** Tibetan Plateau(TP)is the largest and highest terrain on the Earth,comprising more than 80%of continents higher than 4000 m above sea *** extremely high elevation resulted in cold and arid climate,sparse vegetation,limited available water resources,thin oxygen on TP,as well as desolated landscape,which makes it one of the most unfriendly habitable places on the ***,ancient humans lived on TP as early as 200 thousand years ago(Chen et al.,2019;Zhang et al.,2020),and developed ancient civilizations,including the Tibetan Empire,Guge Kingdom in historical periods.

关键词： Tibetan Plateau landscape

Shell-formation mediated surface composition of uniform two-component microparticles fabricated by micro-fluidic spray drying: Effect of component size and solubility

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Particuology 2022年第8期20卷 68-78页

作者： Xiaoqian Ma Shen Yan Shengyu Zhang Quanyi Yin Xiaodong Chen Winston duo wu Engineering Research Centre of Advanced Powder Technology(ERCAPT)School of Chemical and Environmental Engineering College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

This work is aimed to study the effects of component size and solubility on the surface composition of spray dried(SD)uniform two-component particles fabricated by micro-fluidic spray *** precursor liquid consisting of small molecular of methionine(Met,33 g/L)or lysine(Lys,739 g/L)and large-sized silica(12 nm)were prepared by adjusting the mass ratio of components.X-ray energy disper-sive results showed that the respective enrichment degree(De)of Met and Lys on the surface of SD-M1S9 and-L1S9 prepared at 150 C were 182±9% and 125±14%.The De of hydrophobic Met for SD-M1S1 and-M9S1 were 46±9% and 4±2%,respectively,whereas relative hydrophilic Lys mainly distributed internal of the particle meanwhile the De of silica on the surface for SD-L1S1 and-L9S1 were 17±4%and 12±1%,*** temperature(120 and 180℃)showed more apparent effect on the De of amino acid for the particles of less amino *** possible formation mechanism of surface composition and the surface composition impact on the wettability of particles were *** results provide new guidance for manufacturing functional SD powders with various components.

关键词： Spray drying Uniform microparticles Two-component Surface composition Size Solubility

A study of the construction times of the ancient cities in Ganjia Basin,Gansu Province,China

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Journal of Geographical Sciences 2020年第9期30卷 1467-1480页

作者： XIA Huan ZHANG Dongju WANG Qiang wu duo DUAN Yanwu CHEN Fahu Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth Environmental SciencesLanzhou UniversityLanzhou 730000China Key Laboratory of Alpine Ecology Institute of Tibetan Plateau ResearchCASBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences CASBeijing 100101China

The Ganjia Basin in Xiahe County,Gansu Province,China,is located on the northeastern edge of the Tibetan *** area lies in the transitional zone between the Plateau ethnic groups dominated by ancestral Tibetans,and the Central Plains dynasties dominated by ancestral Han in *** Ganjia Basin is therefore well suited to studying the history of the intermixing of the Han and Tibetan *** this study,we collected samples of organic materials from two ancient cities,Bajiaocheng(BJC) and Sirougucheng(SRGC),in the Ganjia Basin,which were used for radiocarbon *** aims were to determine the construction times and function of the cities,based on the radiocarbon ages,Bayesian age modeling,and the analysis of relevant historical *** results are used to discuss the role of the Ganjia Basin in the conflicts between and the integration of the two ethnic groups during the historical *** conclude that BJC was established during 663–732 CE(Common Era);its early occupation history can be divided into an initial establishment phase(670–780 CE) and a phase of regeneration(880–1030 CE).SRGC was probably built at the time of the transition between the Song and Yuan dynasties(~1271 CE).Combining the dating results with an analysis of the architectural styles and historical records,we conclude that BJC was originally built by the Tubo Kingdom as a military stronghold,and its major functions were military,economic and religious,and to support the major eastward expansion of the *** was most likely a temple-focused city intended to promote Tibetan Buddhism which was a major political and religious leadership for the Tibetans at that time,reflecting changes in the status of different religions in the Ganjia *** addition,the intermixing and blending of the Han and Tibetan groups,reflected by the human activities in the Ganjia Basin,was an important demographic and cultural foundation for the formation of the culturally-diverse but spiritually-u

关键词： Ganjia Basin radiocarbon dating Bajiaocheng Sirougucheng ethnic amalgamation Tubo

A rice exocyst subunit gene SEC3A is required for anther dehiscence

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The Crop Journal 2024年第3期12卷 938-943页

作者： Ranran Tu Hong Wang Zhihao Sun Qinwen Zou Jiajun wu duo wu Nan Wang Guanghua He Rice Research Institute Key Laboratory of Application and Safety Control of Genetically Modified CropsAcademy of Agricultural SciencesSouthwest UniversityChongqing 400715China

Anther dehiscence controls optimal interaction between pollen and stigma,thereby determining the successful sexual *** regulators or mechanisms of this process remain ***,two CRISPR/Cas9 mutants of a rice exocyst subunit gene SEC3A,sec3a-1 and sec3a-2,showed anther indehiscence at anthesis and male sterility at *** viability and germination in the mutants were partly defective,whereas their female gametes undergone a normal *** or self-pollinated seeds could be produced by artificial pollination,suggesting potential use of a weak sec3a mutant as a female line during hybrid ***3A is widely expressed in various tissues,including anther *** results showed an excessive IAA accumulation and no endothecium lignification in sec3a-1/2 *** findings suggest that SEC3A appears to regulate anther dehiscence by modulating auxin signaling,providing insights into regulation of anther dehiscence and function of exocyst in plants.

关键词： Rice Male sterility Anther dehiscence Exocyst SEC3A

Effects of climate change and human activity on lake shrinkage in Gonghe Basin of northeastern Tibetan Plateau during the past 60 years

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Journal of Arid Land 2016年第4期8卷 479-491页

作者： wu duo CHEN Fahu LI Kai XIE Yaowen ZHANG Jiawu ZHOU Aifeng College of Earth and Environmental Sciences MOE Key Laboratory of Western China's Environmental SystemsLanzhou University

Changes in the status of freshwater resources are a topic of major global, regional and local concern. This is especially so in the arid and semi-arid regions of China, where shortage of water resources plays a crucial role in limiting sustainable socioeconomic development, as well as in sustaining natural ecosystems. Recent climate change, as well as the effects of localized human activity, such as the use of water for irrigation agriculture, may have significant effects on the status of the water resources in the region. Here, we report the results of a study of changes in the areas of lakes in Gonghe Basin, northeastern Tibetan Plateau of China, over the last 60 years. The data were acquired from optical satellite images and demonstrate that the total water area of lakes in Gonghe Basin decreased significantly from the 1950s to 1980s. The cause is ascribed mainly to human activity including exploitation of farmland, against a background of increasing population; in addition, climatic data for the region demonstrate a minor drying trend during this period as the temperature increased slightly. After the construction of several reservoirs, significant amounts of water were redistributed to promote irrigation agriculture and we conclude that this caused a significant shrinkage of the natural lakes. However, both the area of farmland and the population size remained approximately constant after 1990. We conclude that the variation of the total area of lakes during the second period was mainly controlled by climatic factors （precipitation and temperature）. As the regional temperature reached a new high, the area of some of the lakes decreased sharply before finally maintaining a relatively steady state. We emphasize that anthropogenic climate change and human activity have both significantly influenced the status of water resources in the arid and semi-arid regions of China.

关键词： Gonghe Basin lake shrinkage climate change human activity

Phase transformation of ZrO2 doped with CeO2

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Rare Metals 2018年第1期37卷 66-71页

作者： Bo He Ying Li Hong-Yu Zhang duo-Li wu Li-Hong Liang Hua Wei Schooi of Mechatronics Engineering Shenyang AerospaceUniversityShenyang 110136China Institute of Metal research Chinese Academy of SciencesShenyang 110016China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

Thermal barrier coatings（TBCs） protection is widely used to prolong the lifetime of turbine *** outermost layer of TBCs is ceramic layer, whose function is heat insulation, and the main composition of the ceramic layer is ZrO2. In this study, the micro-Zr02 and the nano-ZrO2 doped with 10 wt% CeO2 as well as microZrO2 and nano-ZrO2 were prepared by air plasma spraying（APS） to study the advantages of the addition of rare earth element. The effect of CeO2 on the phase transformation of ZrO2 was studied. The results show that there are few cracks in micro-and nano-ZrO2 doped with 10 wt% CeO2,and rare earth oxides can affect the phase transformation significantly. The morphologies, hardness and elastic modulus of the four ceramic layers were also discussed.

关键词： Ceramic layer Rare earth oxides Phase transformation CeO2

Holocene temperature variation recorded by branched glycerol dialkyl glycerol tetraethers in a loess-paleosol sequence from the north-eastern Tibetan Plateau

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Frontiers of Earth Science 2023年第4期17卷 1012-1025页

作者： Tianxiao WANG duo wu Tao WANG Lin CHEN Shilong GUO Youmo LI Chenbin ZHANG Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Alpine Paleoecology and Human Adaptation Group(ALPHA) Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Reconstructing Holocene temperature evolution is important for understanding present temperature variations and for predicting future climate change,in the context of global *** evolution of Holocene global temperature remains disputed,due to differences between proxy reconstructions and model simulations,a discrepancy known as the῾Holocene temperature conundrum᾽.More reliable and quantitative terrestrial temperature records are needed to resolve the spatial heterogeneity of existing *** this study,based on the analysis of branched glycerol dialkyl glycerol tetraethers(brGDGTs)from a loess-paleosol sequence from the Ganjia Basin in the north-eastern Tibetan Plateau(NETP),we quantitatively reconstructed the mean annual air temperature(MAAT)over the past 12 *** MAAT reconstruction shows that the temperature remained low during the early Holocene(12−8 ka),followed by a rapid warming at around 8 *** 8 to 4 ka,the MAAT record reached its highest level,followed by a cooling trend from the late Holocene(4−0 ka).The variability of the reconstructed MAAT is consistent with trends of annual temperature records from the Tibetan Plateau(TP)during the *** attribute the relatively low temperatures during the early Holocene to the existence of ice sheets at high-latitude regions in the Northern Hemisphere and the weaker annual mean insolation at 35°*** the mid to late Holocene,the long-term cooling trend in the annual temperature record was primarily driven by declining summer *** study provides key geological evidence for clarifying Holocene temperature change in the TP.

关键词： sHolocene Ganjia Basin loess temperature variation BrGDGTs

Solvent-free nanocasting toward universal synthesis of ordered mesoporous transition metal sulfide@N-doped carbon composites for electrochemical applications

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Nano Research 2019年第9期12卷 2250-2258页

作者： Jiahui Zhu Zhi Chen Lin Jia Yuqi Lu Xiangru Wei Xiaoning Wang Winston duo wu Na Han Yanguang Li Zhangxiong wu Suzhou Key Laboratory of Green Chemical Engineering School of Chemical and Environmental EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Institute of Functional Nano and Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China

Transition metal sulfides (TMSs) have a wide range of applications owing to their intriguing *** efforts have been devoted to nanostructuring TMSs to enhance their properties and performance,still there is a high need in general synthesis of TMS ***,for the first time,a simple solvent free reactive nanocasting approach that integrates solid precursor loading,in-situ sulfuration and carbonization into a single heating step is developed for the universal synthesis of ordered mesoporous TMS@N-doped carbon composites (denoted as OM-TMS@NCs) with methionine (Met) and metal chlorides as the precursors and the mesoporous silica (SBA-15) as the hard template.A series of OM-TMS@NCs with a hexagonal mesostructure,ultra-high surface areas (430-754 m2·g-1),large pore volumes (0.85-1.32 cm3·g-1),and unique TMS stoichiometries,including MoS2,Fe7S8,Co9S8,NiS,Cu7S4 and ZnS,are *** distinct structure configurations,namely,highly dispersed ultrathin TMS nanosheets within NCs and TMS@NC co-nanowire arrays,can be obtained depending on different *** structure evolution of the OM-TMS@NCs over the solvent-free nanocasting process is studied in detail for a deep understanding of the *** demonstrations,these materials are promising for electrocatalytic hydrogen evolution reaction and lithium ion storage with high performances.

关键词： transition metal sulfides mesoporous materials solvent-free nanocasting in-situ sulfuration carbon-based composites electrochemical applicati ons