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Dispersal of the Zh.j.ang River(Pearl River) derived sediment in the holocene

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Acta Oceanologica Sinica 2014年第8期33卷 1-9页

作者： GE qian LIU j.P. XUE Zuo ChU Fengyou Key Laboratory of Submarine Geosciences State Oceanic AdministrationSecond Institute of OceanographyState Oceanic Administration Department of Marine Earth and Atmospheric SciencesNorth Carolina State UniversityRaleighNC 27695USA

high-resolution Chirp profiling and coring reveals an elongated （ca. 400 km） holocene Zh.j.ang River （Pearl River）-derived mud area （maximum thickness 〉 20 m） extending from the Zh.j.ang River Delta, southwest-ward off the Guangdong coast, to the Leizhou Peninsula. Two depo-centers, one proximal and one distal, are identified. On the continental shelf off the west Guangdong Province, the mud is deposited in water depth shallower than 50 m; while to the southeast of the Zh.j.ang River Estuary, the mud area can extend to the -120 m isobath. A combined analysis with the stratigraphic sequences of other muddy deposits in the West-ern Pacific marginal seas （mainly Changjiang （Yangtze） and huanghe （Yellow） Rivers derived） indicates that the initiation of the Zh.j.ang River muddy deposit can be further divided into two stages： Stage 1 is before the mid-holocene sea-level highstand （ca. 7.0 cal. ka BP）, the proximal mud was mostly deposited after 9.0 cal. ka BP, when the sea-level rose slowly after the Meltwater Pulse -1C; Stage 2, after the mid-holocene sea-level highstand, clinoform developed on the continental shelf off the west Guangdong Province, extending ca. 400 km from the Zh.j.ang River Estuary. The proximal clinoform thins offshore, from ca. 10 m thickness around 5-10 m water depth to less than 1-2 m around 20-30 m water depth. In addition, we also find a de-veloped distal clinoform in the east of the Leizhou Peninsula.

关键词： South China Sea Zh.j.ang River mud clinoform

Advances and challenges in developing cocatalysts for photocatalytic conversion of carbon dioxide to fuels

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Nano Research 2022年第12期15卷 10090-10109页

作者： qian Wang Zhenhua Pan Graduate School of Engineering Nagoya UniversityFuro-choChikusa-kuNagoya464-8603Japan Institute for Advanced Research Nagoya UniversityFuro-choChikusa-kuNagoya464-8601Japan Department of Applied Chemistry Faculty of Science and TechnologyChuo University1-13-27 KasugaBunkyoTokyo112-8551Japan

The global adoption of efficient sustainable energy sources is a crucial step toward meeting energy demands while achieving carbon emission reduction *** energy has become a clean and cost-competitive alternative to traditional fossil fuels,but the intermittent nature of sunlight results in challenges associated with energy storage and *** carbon dioxide reduction intends to mimic natural photosynthesis for utilizing sunlight to chemically convert water and CO_(2) into *** this process,the solar energy is captured and stored in fuels,so-called solar fuels,for widespread on-demand *** solar fuel production systems are multi-component,comprising light-harvesting(photosensitizer)and catalytic(cocatalyst)*** are indispensable for photocatalytic CO_(2) reduction systems,which promote charge carrier separation and transport,reduce the reaction activation energy,and alter the reaction route,thereby enhancing the activity and selectivity of the photocatalytic *** review presents a comprehensive summary of the recent advancements in cocatalysts for photocatalytic CO_(2) reduction reaction(CO_(2)RR),with the purpose of providing new insights and guidance to the field with regard to research directions and best *** summarize how various cocatalysts including inorganic nanoparticles,metal complexes,enzymes,and bacteria can be combined with semiconductor photosensitizer for light-driven photocatalytic CO_(2)***-by-side comparisons reveal the strengths and limitations of each kind of cocatalysts and how lessons extracted from studying natural photosynthetic systems can be applied to investigations of artificial photosynthesis,presenting an outlook discussing possible future concepts for a more effective photocatalytic CO_(2) reduction process.

关键词： photocatalysis cocatalyst carbon dioxide reduction artificial photosynthesis solar fuel production

Network Embedding Algorithm for Vulnerability Assessment of Power Transmission Lines Using Integrated Structure and Attribute Information

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CSEE journal of Power and Energy Systems 2024年第1期10卷 351-360页

作者： Xianglong Lian Tong qian Zepeng Li Xingyu Chen Wenhu Tang Q.h.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

In power systems,failures of vulnerable lines can trigger large-scale cascading failures,and vulnerability assessment is dedicated to locating these lines and reducing the risks of such *** on a structure and attribute network embedding(SANE)algorithm,a novel quantitative vulnerability analysis method is proposed to identify vulnerable lines in this ***,a two-layered random walk network with topological and electrical properties of transmission lines is ***,based on the weighted degree of nodes in the two-layered network,the inter-layer and intra-layer walking transition probabilities are developed to obtain walk ***,a Word2Vec algorithm is applied to obtain lowdimension vectors representing transmission lines,according to obtained walk sequences for calculating the vulnerability index of transmissions ***,the proposed method is compared with three widely used methods in two test *** show the network embedding based method is superior to those comparison methods and can provide guidance for identifying vulnerable lines.

关键词： Network embedding random walk transmission lines vulnerability assessment

Elastic and Seismic Properties of Dabie-Sulu Ultrahigh Pressure Metamorphic Rocks

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 20-37页

作者： WANG qian jI Shaocheng SUN Shengsi Matthew h.SALISBURY hartmut KERN State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Departement des Genies Civil Geologique et des MinesEcole Polytechnique de Montreal Montreal H3C 3A7Canada State Key Laboratory of Continental Tectonics and Dynamics Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Geological Survey of Canada-Atlantic Bedford Institute of OceanographyDartmouth B2Y 4A2Canada Institutfur Geowissenschaften Universitat Kiel24098 KielGermany

Lame modulus （λ） and shear modulus （μ） are among the most important, intrinsic, elastic constants of rocks. Using 7. and μ could be much more advantageous than using P- and S-wave velocities （Vp and Vs）. here we quantified these equivalent isotropic elastic moduli for 115 representative rocks from the ultrahigh pressure （UhP） metamorphic terrane of the Dabie-Sulu orogenic belt （China） and their variations with pressure （P）, temperature （T）, density （p）, Vp, Vs and mineralogical composition. Both moduli increase nonlinearly and linearly with increasing pressure at low （〈200-300 MPa） and high （〉200-300 MPa） pressures, respectively. In the regime of high pressures, 7. and IX decrease quasi-linearly with increasing temperature with temperature derivatives dλ/dT and dμ/dT generally in the range of -10×10-3 to -1×10-3 GPa/℃. Dehydration of water-bearing minerals such as serpentine in peridotites and chlorite in retrograde eciogites results in an abrupt drop in 7. while μ remains almost unchanged. In Z-p, μ-p and 7.-IX plots, the main categories of UhP rocks can be characterized. Serpentinization leads to significant decreases in μ and 7. as serpentine has extremely low values of Z, μ and p. Eclogites, common mafic rocks （mafic gneiss, metagabbro and amphibolite）, and felsic rocks （orthogneiss and paragneiss） have high, moderate and low μ and λ values, respectively. For pyroxenes and olivines, λ increases but μ decreases with increasing Fe/Mg ratios. For plagioclase feldspars, both Z and μ exhibit a significant positive correlation with anorthite content. SiO2-rich felsic rocks and quartzites are deviated remarkably from the general trend lines of the acid-intermediate-mafic rocks in Vs-p, μ-p, λ-Vp,λ-Vs and μ-λ diagrams because quartz has extremely low λ （-8.1 GPa） and p （2.65 g/cm3） but moderate μ （44.4 GPa） values. Increasing the contents of garnet, rutile, ilmenite and magnetite results in a significant increase in the λ and μ values of the UhP metamorphic rocks. howev

关键词： seismic properties elastic constants ultrahigh pressure metamorphic rocks Dabie-Sulu,deep continental roots

Model optimization method and connected-pipe experiment of a liquid fuel ramjet engine

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航空动力学报 2013年第6期28卷 1277-1285页

作者： MA qian-rong GUO Xin WU hu ChOU qian School of Power and Energy Northwest Polytechnical University Aero-Engine Altitude Simulated Key Laboratory China Gas Turbine EstablishmentAviation Industry Corporation of China

The optimization method of a mathematical model and connected-pipe experimental technique for a test in altitude test facility (ATF) of a liquid fuel ramjet engine was *** optimization of the simple mathematical model was divided into two ***,using the test engine's geometry configuration size data,a preliminary adjustment was ***,using experimental test data,the components' experiential coefficients were modified *** was laid on the simulation technique of flight condition and parameters measurement *** experimental technique was applied to a ramjet ATF test *** comparison results show that the optimized-model has higher precision and the nozzle gross thrust difference drops from 12% to about 4%.

关键词： ramjet engine model optimization altitude test facility(ATF) connected-pipe experiment simulation technique

A comparison study of Ce/La and Ca microalloying on the bio-corrosion behaviors of extruded Mg-Zn alloys

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journal of Magnesium and Alloys 2020年第4期8卷 1269-1280页

作者： j.h.Chu L.B.Tong Z.h.j.ang D.N.Zou Q.j.Wang S.F.Liu h.j.Zhang School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055China State Key Laboratory of Rare Earth Resources Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Lab of Automobile Materials College of Materials Science and EngineeringJilin UniversityNanling CampusChangchun 130025China

The influences of Ca and Ce/La microalloying on the microstructure evolution and bio-corrosion resistances of extruded Mg-Zn alloys have been systematically investigated in the current *** with single Ca or Ce/La addition,the Ca-Ce/La cooperative microalloying results in an outstanding grain refinement,because the fine secondary phase particles effectively hinder the recrystallized grain *** coarse Ca2Mg6Zn3 phases promote the formation of Ca3(PO4)2 or hydroxyapatite particles during the immersion process and accelerate the dissolution of the corrosion product film,which destroys its integrity and results in the deterioration of anti-corrosive *** Ce/La elements can be dispersed within the conventional Mg7Zn3 phases,which reduce the internal galvanic corrosion between Mg matrix and the secondary phases,leading to an obvious improvement of corrosion ***,the Ca-Ce/La cooperative microalloying achieves a homogenous fine-grained microstructure and improves the protective ability of surface film,which will pave a new avenue for the design of biomedical Mg alloys in the coming future.

关键词： Extruded Mg-Zn alloy Ca and Ce/La microalloying Microstructure evolution Bio-corrosion behaviors

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