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Asymmetric or diffusive co-evolution generates meta-populations in fig-fig wasp mutualisms

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Science China(life Sciences) 2014年第6期57卷 596-602页

作者： WANG RuiWu YANG Yan WIGGINS Natasha l. State Key laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences School of Plant Science University of Tasmania

Co-evolutionary theory assumes co-adapted characteristics are a positive response to counter those of another species,whereby co-evolved species reach an evolutionarily stable interaction through bilateral ***,evidence from the fig-fig wasp mutualistic system implies very different co-evolutionary selection mechanisms,due to the inherent conflict among interacted *** plants appear to have discriminatively enforced fig wasps to evolve"adaptation characteristics"that provide greater benefit to the fig,and fig wasps appear to have diversified their evolutionary strategies in response to discriminative enforcement by figs and competition among different fig wasp *** what appears to be an asymmetric interaction,the prosperity of cooperative pollinating wasps should inevitably lead to population increases of parasitic individuals,thus resulting in localized extinctions of pollinating *** response,the sanctioning of parasitic wasps by the fig should lead to a reduction in the parasitic wasp *** meta-populations created by such asymmetric interactions may result in each population of coevolved species chaotically oscillated,temporally or evolutionarily.

关键词： asymmetric co-evolution inter-specific cooperation meta-population mutualism

Healing Process of Casting Pores in a Ni-based Superalloy by Hot Isostatic Pressing

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Journal of Materials Science & Technology 2015年第11期31卷 1151-1157页

作者： X.G.Zheng Y.-N.Shi l.H.lou Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Superalloy Division Institute of Metal Research Chinese Academy of Sciences

Hot isostatic pressing （HIP） with a pressure of 180 MPa at a temperature of 1170 ℃ was introduced to an investment cast Ni-based superalloy （Mgl） turbocharger blade to explore the healing process of casting pores generated during investment casting. Optical micrograph and scanning electron naicroscopy （SEM） observations indicate that eutectic pores are the main cast defects in the as-cast blade before HIP. These pores normally locate at the solidification front of γ/γ＇ eutectic with a size of a few micrometers to a few tens of micrometers. After HIP for 4 h, most of the pores were closed. Based on phase characteristics, these pores were healed by the formation of γ matrix with finer and irregular-shaped γ＇ precipitates. Healing interface can be easily distinguished by SEM. line scan by using energy dispersive X-ray spectroscopy （EDS） reveals a much higher Ti and Al concentration in the healing interface. It is proposed that solute diffusion toward the casting pores during HIP results in the formation of γ, and the much higher concentration of γ＇-forming elements Al and Ti near the healing interface contributes to the precipitation of γ＇ in the healed region in the succeeding cooling process after HIP.

关键词： Superalloy Hot isostatic pressing (HIP) Healing

Flow Characteristics of Crude Oil with High Water Fraction during Non-heating Gathering and Transportation

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China Petroleum Processing & Petrochemical Technology 2021年第1期23卷 88-97页

作者： lüYuling Tan Hao li Jiao Yang Donghai Xu Peiyang Shandong Key laboratory of Oil&Gas Storage and Transportation Safety China University of Petroleum(East China)Qingdao 266580 China Resources(Zhengzhou)Municipal Engineering Design&Research Institute Co. Ltd.

In order to ensure the safety of the non-heating gathering and transportation processes for high water fraction crude oil,the effect of temperature,water fraction,and flow rate on the flow characteristics of crude oil with high water fraction was studied in a flow experimental system of the X *** distinct flow patterns were identified by the photographic and local sampling ***,three new flow patterns were found to occur below the pour point of crude oil,including ew/O&W stratified flow with gel deposition,ew/O&W intermittent flow with gel deposition,and water single-phase flow with gel ***,two characteristic temperatures,at which the change rate of pressure drop had changed obviously,were found during the change of pressure *** characteristic temperature of the first congestion of gel deposition in the pipeline was determined to be the safe temperature for the non-heating gathering and transportation of high water cut crude oil,while the pressure drop reached the peak at this *** empirical formula for the safe temperature was established for oil-water flow with high water fraction/low fluid production *** results can serve as a guide for the safe operation of the non-heating gathering and transportation of crude oil in high water fraction oilfields.

关键词： crude oil with high water fraction non-heating gathering and transportation flow pattern pressure drop safe temperature

Industrial transformation and green production to reduce environmental emissions: Taking cement industry as a case

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Advances in Climate Change Research 2015年第3期6卷 202-209页

作者： lü Yong-long GENG Jing HE Gui-Zhen State Key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Eco-Civilization Research Center Sanya University

Industrial transformation and green production(ITGP) is a new 10-year international research initiative proposed by the Chinese National Committee for Future Earth. It is also an important theme for adapting and responding to global environmental change. Aiming at a thorough examination of the implementation of ITGP in China, this paper presents its objectives, its three major areas, and their progress so far. It also identifies the key elements of its management and proposes new perspectives on managing green transformation. For instance, we introduce a case study on cement industry that shows the positive policy effects of reducing backward production capacity on PCDD/Fs emissions. Finally,to develop different transformation scenarios for a green future, we propose four strategies: 1) policy integration for promoting green industry, 2)system innovation and a multidisciplinary approach, 3) collaborative governance with all potential stakeholders, and 4) managing uncertainty,risks, and long-time horizons.

关键词： Industrial transformation Green industrial policy Backward production capacity Cement industry China

Spatiotemporal spectrum and momentum flux of the stratospheric gravity waves generated by a typhoon

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Science China Earth Sciences 2013年第5期56卷 54-62页

作者： CHEN Dan CHEN ZeYu lü DaRen Key laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences College of Atmospheric Sciences Nanjing University of Information Science & Technology

The simulation results of Typhoon Matsa （2005） by using the Weather Research and Forecasting （WRF） model show that pro- nounced stratospheric gravity waves （GWs） are generated in the vicinity of the typhoon. Using the model output, we investi- gate the spatial structures and the temporal variations of the GWs through a three dimensional （3-d） spectral analysis, i.e. the spectrum with respect to two horizontal wavenumbers and frequency. We further derive the momentum flux carried by the GWs. Spectral investigation results show that the power spectral density （PSD） of the GWs exhibits a single-peaked spectrum, which consists primarily of a distinct spectrum at horizontal wavelength of -1000 km, time period of 12-18 h, and vertical wavelength of 7-9 kin. This spectrum is different from the spectra of GWs generated by deep convections disclosed by the previous researches. Both the PSD and momentum flux spectrum are prominent in positive kh portion, which is consistent with the fact that the GWs propagate in the upstream of mean flow. large momentum flux is found to be associated with the GWs, and the net zonal momentum flux is 0.7845×10-3 Pa at 20 km height, which can account for -26% of the momentum flux that is required in driving the QBO phenomenon.

关键词： stratospheric gravity waves typhoon 3-d spectrum PSD momentum flux

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Cyprinid phylogeny based on Bayesian and maximum likelihood analyses of partitioned data:implications for Cyprinidae systematics

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Science China(life Sciences) 2012年第9期55卷 761-773页

作者： WANG XuZhen GAN XiaoNi lI JunBing MAYDEN Richard l. HE ShunPing Key laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Department of Biology Saint Louis UniversitySaint LouisMissouri 63103-2010USA

Cyprinidae is the biggest family of freshwater fish, but the phylogenetic relationships among its higher-level taxa are not yet fully resolved. In this study, we used the nuclear recombination activating gene 2 and the mitochondrial 16S ribosomal RNA and cytochrome b genes to reconstruct cyprinid phylogeny. Our aims were to （i） demonstrate the effects of partitioned phylo- genetic analyses on phylogeny reconstruction of cyprinid fishes; （ii） provide new insights into the phylogeny of cyprinids. Our study indicated that unpartitioned strategy was optimal for our analyses; partitioned analyses did not provide better-resolved or -supported estimates of cyprinid phylogeny. Bayesian analyses support the following relationships among the major mono- phyletic groups within Cyprinidae：（Cyprininae, labeoninae）, （（Acheilognathinae, （（leuciscinae, Tincinae）, Gobioninae））, Xenocyprirlinae）. The placement of Danioninae was poorly resolved. Estimates of divergence dates within the family showed that radiation of the major cyprinid groups occurred during the late Oligocene through the late Miocene. Our phylogenetic analyses improved our understanding of the evolutionary history of this important fish family.

关键词： Cyprinidae phylogeny molecular dating partitioned analyses

Diversification of Sisorid catfishes(Teleostei: Siluriformes)in relation to the orogeny of the Himalayan Plateau

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Science Bulletin 2016年第13期61卷 991-1002页

作者： Chuanjiang Zhou Xuzhen Wang Xiaoni Gan Yaping Zhang David M.Irwin Richard l.Mayden Shunping He Key laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of Sciences Key laboratory of Freshwater Fish Reproduction and Development (Southwest University) Ministry of EducationSchool of Life Science Southwest University State Key laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences College of Fisheries Henan Normal University Department of laboratory Medicine and Pathobiology University of Toronto Banting and Best Diabetes Centre University of Toronto Department of Biology 3507 Laclede Ave. Saint Louis University

Abstract Sisorid catfishes are primarily limited in distribution to rivers of the Himalayan region and Tibetan Plateau. These species have external morphologies that are adapted for extremely fast-flowing riverine systems. Given the diversity of the group and the above qualities of these catfishes, this lineage serves as an ideal group for inferring the geological history of this region based on their phylogenetic relationships reflecting evolu- tionary history. We sequenced the complete mitochondrial genome and four nuclear genes of representative sisorids distributed across river systems in China. Phylogenetic analyses strongly support the monophyly of the Sisoridae and the glyptosternoids. An analysis of the reconstructed ancestral states derived from inferred genealogical relationships suggests that the evolution of this lineage was accompanied by convergent evolution in morphological traits that were presumably in response to environmental pressure involving the rapid flowing river system that were generated during the uplift of the Tibetan Plateau （UTP）. Molecular dating indicates that the Chinese sisorids and the glyptosternoids originated at the later Miocene （~ 10.9-9.8 Mya）, and with further biogeographic analyses indicates that the species of Sisoridae likely originated from a widely distributed ancestor. Moreover, the divergence of the Sisoridae in China can be divided into two phases consis- tent with the UTP. All of these results indicate that the diversification and dispersal events in this lineage occurred as a result of drainage systems formed during and after the UTP in the late Miocene and Quaternary periods.

关键词： Phylogeny. Diversification and dispersal.Biogeography - Divergence time estimation ~ TibetanPlateau ~ Sisoridae ~ Catfish

Developing a sustainable strategy to conserve reservoir marginal landscapes

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National Science Review 2018年第1期5卷 10-14页

作者： Qiang Tang Bojie Fu Adrian l.Collins Anbang Wen Xiubin He Yuhai Bao Key laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and Environment Chinese Academy of Sciences State Key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

China has accelerated its pace in building dams to meet growing demands in energy consumption,as well as to alleviate air pollution resulting from fossil fuel emissions and to mitigate global climate change *** rivers in southwestern China(*** Jinsha,Yalong,Dadu,Wu,Nu,lancang and upper Yangtze rivers)have primarily been targeted as major basins for hydropower development,where cascade dams have been constructed or are *** them,the Three Gorges Dam is the world’s largest hydropower project

关键词： Developing a sustainable strategy to conserve reservoir marginal landscapes

The Caucasian-Arabian segment of the Alpine-Himalayan collisional belt: Geology, volcanism and neotectonics

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Geoscience Frontiers 2015年第4期6卷 513-522页

作者： E.Sharkov V.lebedev A.Chugaev l.Zabarinskaya A.Rodnikov N.Sergeeva I.Safonova Institute of Geology of Ore Deposits Petrography Mineralogy and Geochemistry RAS Staromonetny Line 35 Moscow 119017 Russia Geophysical Center of RAS Molodezhnaya St. 3 Moscow 119296 Russia Institute of Geology and Mineralogy SB RAS Koptyuga Ave. 3 Novosibirsk 630090 Russia Novosibirsk State University Pirogova St.2 Novosibirsk 630090 Russia

The Caucasian-Arabian belt is part of the huge late Cenozoic Alpine-Himalayan orogenic belt formed by collision of continental plates. The belt consists of two domains： the Caucasian-Arabian Syntaxis （CAS） in the south and the ew-striking Greater Caucasus in the north. The GAS marks a zone of the indentation of the Arabian plate into the southern East European Craton. The Greater Caucasus Range is located in the south of the Eurasian plate; it was tectonically uplifted along the Main Caucasian Fault （MCF）, which is, in turn, a part of a megafault extended over a great distance from the Kopetdag Mts. to the Tornquist- Teisseyre Trans-European Suture Zone. The Caucasus Mts. are bounded by the Black Sea from the west and by the Caspian Sea from the east. The SN-striking CAS is characterized by a large geophysical isostatic anomaly suggesting presence of mantle plume head. A 500 km long belt of late Cenozoic volcanism in the CAS extends from the eastern Anatolia to the lesser and Greater Caucasus ranges. This belt hosts two different types of volcanic rocks：（1） plume-type intraplate basaltic plateaus and （2） suprasubductiontype calc-alkaline and shoshonite-latite volcanic rocks. As the CAS lacks signatures of subduction zones and is characterized by relatively shallow earthquakes （50 60 kin）. we suggest that the ＂supra- subduction-type＂ magmas were derived by interaction between mantle plume head and crustal material. Those hybrid melts were originated under conditions of collision-related deformation. During the late Cenozoic, the width of the CAS reduced to ca. 400 km due to tectonic ＂diffluence＂ of crustal material Drovided bv the continuing Arabia-Eurasia collision.

关键词： East European CratonCalc-alkaline and shoshonite-latitevolcanismMantle plume headBasaltic plateausPlume-crust interactionTectonic "diffluence"