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Frontiers of Environmental science & Engineering 2015年第5期9卷 879-887页

作者： Yuling cai school of chemistry and Environment South China Normal University Guangzhou 510006 China Guangdong Technology Research centre for Ecological Management and Remediation of Urban Water system Guangzhou 510006 China Department of science and Environmental studies Hong Kong Institute of Education Hong Kong 00852 China

As a promising in situ remediation technology, nanoscale zero-valent iron （nZVI） can remove polybromi- nated diphenyl ethers such as decabromodiphenyl ether （BDE209） effectively, However its use is limited by its high production cost. Using steel pickling waste liquor as a raw material to prepare nanoscale zero-valent metal （nZVM） can overcome this deficiency. It has been shown that humic acid and metal ions have the greatest influence on remediation. The results showed that nZVM and nZVI both can effectively remove BDE209 with little difference in their removal efficiencies, and humic acid inhibited the removal efficiency, whereas metal ions promoted it. The promoting effects followed the order Ni2＋〉 cu2＋〉 co2＋ and the cumulative effect of the two factors was a combination of the promoting and inhibitory individual effects. The major difference between nZVM and nZVI lies in their crystal form, as nZVI was found to be amorphous while that of nZVM was crystal. However, it was found that both nZVM and nZVI removed BDE209 with similar removal efficiencies. The effects and cumu- lative effects of humic acid and metal ions on nZVM and nZVI were very similar in terms of the efficiency of the BDE209 removal.

关键词： steel pickling waste liquor nanoscale zero-valet metal nanoscale zerovalent iron humic acid metalion

Overpressure development and oil charging in the central Junggar Basin,Northwest china:Implication for petroleum exploration

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science china Earth sciences 2009年第11期52卷 1791-1802页

作者： XiYuan cai china Petroleum & chemical corporation Beijing 100092 China

The Junggar Basin is one of the largest and most petroliferous superimposed petroleum basins in china. The central depression area has become the frontier field for petroleum exploration. The characteristics of potential source rocks and reservoir sandstones, and the pressure regime in the central Junggar Basin were studied. Permian shales are dominated by hydrogen-rich, oil-prone algal organic matter, and Jurassic mudstones are dominated by hydrogen-poor, higher-plant derived organic matter. These source rocks are widespread and have been mature for hydrocarbon generation, suggesting good to excellent exploration potential, both for crude oils and for natural gases. The deeply buried Jurassic sandstones usually have low porosity and permeability. However, sandstones beneath the Jurassic/cretaceous unconformity display relatively high porosity and permeability, suggesting that meteoric water leaching had improved the quality of the sandstones. Overpressure developed over much of the central Junggar Basin. The overpressured rocks are characterized by slightly increased interval transit time, low sandstone permeability, increased organic matter maturity, and high relative hydrocarbon-gas contents. Mudstones in the overpressured system have quite the same clay mineral compositions as mudstones in the lower part of the normally pressured system. Overpressure generation in the central Junggar Basin is best to be explained as the result of hydrocarbon generation and fluid retention in low-permeability rocks. Petroleum generated from Permian and Jurassic source rocks could migrate laterally through preferential petroleum migration pathways and accumulated in structural traps or lithological traps in the overpressured system, or migrate vertically through faults/ hydraulic fractures into the overlying, normally pressured system and accumulate in structural or lithological traps. Therefore, commercial petroleum reservoirs could be potentially found in both the overpressured

关键词： pressure regime overpressure generation oil charge petroleum exploration potential Junggar Basin

Greenhouse gas budget for terrestrial ecosystems in china

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science china Earth sciences 2012年第2期55卷 173-182页

作者： cai Zucong state Key Laboratory of soil and sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Terrestrial ecosystems may act as a source or a sink for the atmospheric greenhouse gases, carbon dioxide (cO2), methane (cH4), and nitrous oxide (N2O), depending on land use and management. This paper reviews the literature on carbon, cH4, and N2O fluxes from terrestrial ecosystems in china, and analyzes its national greenhouse gas budget. carbon storage in biomass and soils in chinese terrestrial ecosystems decreased in the past 300 years, due to deforestation and expansion of cultivated land, and reached a minimum in the late 1970s. since then, carbon storage has increased at an estimated rate of 0.19 to 0.26 Pg c yr-1, mainly owing to reforestation and afforestation. cH4 emission from natural wetlands decreased from 6.65 Tg cH4 yr-1 in 1990 to 5.71 Tg cH4 yr-1 in 2000 owing to the decrease in wetland area. cH4 emission from flooded rice fields was 7.41 Tg cH4 yr-1. At the same time, aerobic soils took up atmospheric cH4 at a rate of 2.56 Tg cH4 yr-1. Nitrous oxide emission from forestlands, grasslands, and farmlands was positively correlated with precipitation at a national scale, and the emission rate was positively correlated with the cH4 uptake rate of forestlands and grasslands (Psources were estimated to be 419 Gg N yr-1 and anthropogenic sources (from farmlands) to be 292 to 476.3 Gg N yr-1, with a mean of 372.6 Gg N yr-1. The integrated budget of greenhouse gasses indicates that chinese terrestrial ecosystems act as a small net sink for global warming potential (GWP), ranging from 0.04 to 0.32 Pg cO2-eq yr-1, in a striking contrast to terrestrial ecosystems globally, which are a source of 2.75 to 6.78 Pg cO2-eq yr-1. The ratios of anthropogenic to natural sources of cH4 and N2O are much larger in chinese terrestrial ecosystems than they are in global averages, reflecting greater human disturbance of terrestrial ecosystems in china.

关键词： terrestrial ecosystems carbon dioxide methane nitrous oxide

Viscosity Iterative Algorithm for Variational Inequality Problems and Fixed Point Problems of strict Pseudo-contractions in Uniformly smooth Banach spaces

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Acta Mathematica sinica,English series 2015年第9期31卷 1435-1448页

作者： Gang cai college of Mathematics science Chongqing Normal University

The purpose of this paper is to study a new viscosity iterative algorithm based on a generalized contraction for finding a common element of the set of solutions of a general variational inequality problem for finite inversely strongly accretive mappings and the set of common fixed points for a countable family of strict pseudo-contractions in uniformly smooth Banach spaces. We prove some strong convergence theorems under some suitable conditions. The results obtained in this paper improve and extend the recent ones announced by many others in the literature.

关键词： Variational inequality fixed point strong convergence uniformly smooth Banach space

Macro to nanoscale deformation of transformation-induced plasticity steels：Impact of aluminum on the microstructure and deformation behavior

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Journal of Materials science & Technology 2018年第5期34卷 745-755页

作者： V.s.Y.Injeti Z.c.Li B.Yu R.D.K.Misra Z.H.cai H.Ding Department of Metallurgical Materials and Biomedical Engineering500 W. University Avenue USA school of Materials science and Engineering Northeastern University Shenyang 110819 China

This work aims to elucidate the impact of aluminum-content on microstructure and deformation mechanisms of transformation-induced plasticity（TRIP） steels through macroscale and nanoscale deformation experiments combined with post-mortem electron microscopy of the deformed *** solid-state transformation-induced mechanical deformation varied with the Al contents,and influenced tensile strength-ductility *** with 2–4 wt% Al were characterized by TRIP *** contrast to 2 Al-TRIP and 4 Al-TRIP steels,twinning-induced plasticity（TWIP） was also observed in conjunction with strain-induced martensite in 6 Al-TRIP *** behavior is attributed to the increase in stacking fault energy with the increase of Al content and stability of austenite,which depends on the local chemical *** study addresses the knowledge gap with regard to the effect of Al content on austenite stability in medium-Mn TRIP *** combination is expected to potentially enable cost-effective alloy design with high strength-high ductility condition.

关键词： Medium-manganese steels Aluminum content Electron microscopy Mechanical properties Nanoscale deformation TRIP steel Twinning

Bulk nanocrystalline W-Ti alloys with exceptional mechanical properties and thermal stability

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Journal of Materials science & Technology 2022年第19期114卷 16-28页

作者： H.X.Xue X.c.cai B.R.sun X.shen c.c.Du X.J.Wang T.T.Yang s.W.Xin T.D.shen clean Nano Energy center State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China cssc 723rd Research Institute China State Shipbuilding Corporation LimitedYangzhou 225000China

Nanocrystalline(Nc)W metals and alloys often exhibit higher radiation tolerance and strength than their coarse-grained ***,their thermal stability is low,making it difficult to achieve bulk Nc W metals and alloys by consolidation using conventional techniques such as pressure-less sintering,hot-explosive-compaction sintering,and spark plasma *** we report the synthesis and mechanical properties of bulk Nc W_(100-x)Ti_(x)(x=10 at.%-30 at.%)alloys prepared by consolidating mechanically alloyed Nc powders under a high-temperature/high-pressure *** 20 at.%-30 at.%Ti largely improves the sinterability of Nc W-Ti alloy *** room-temperature microhardness and compressive yield strength of consolidated bulk Nc W_(80)Ti_(20) alloy are∼16.9 and 6.0 GPa,respectively,which are mainly caused by grain boundary strengthening and significantly higher than those of previously reported W and W *** ultimate compressive strength of bulk Nc W_(80)Ti_(20) measured between 900 and 1100°c deceases with increasing *** behavior can be explained by the activation of Rachinger grain boundary *** grain growth is observed in bulk Nc W_(80)Ti_(20) after compression at 1000°*** calculation suggests that it is the segregation of Ti at grain boundaries that decreases the specific grain boundary free energy and makes the Nc W_(80)Ti_(20) alloy thermodynamically stable.

关键词： Nanocrystalline W-Ti alloys segregation Grain boundary energy strength Hardness

Renewable Energies, Present & Future

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电工电能新技术 2005年第1期24卷 69-75页

作者： X. s. cai Fellow IEEE E.E. Dept. Tsinghua University Beijing 100084 China

Fossil fuels are major cause of environmental destruction in pollutions. It has created much needed momentum for renewable energies, which are environmentally benign, generated locally, and can play a significant role in developing economy. As a sustainable energy sources, it can grow at a rapid pace to meet increasing demands for electricity in a cost-effective way.

关键词：风力发电太阳能发电能源利用可再生能源

Percolation of Mobile Individuals on Weighted scale-Free Networks

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chinese Physics Letters 2011年第11期28卷 278-281页

作者： WU An-cai Department of Physics Harbin Institute of TechnologyHarbin 150006

The percolation-like phase transition of mobile individuals is studied on weighted scale-free(WsF)networks,in which the maximum occupancy at each node is one individual(*** core interaction)and individuals can move to neighbor void ***,the condition for the existence of a spanning cluster of individuals(a connected cluster of neighbor nodes occupied by individuals that span the entire systems)is investigated and it is found that there exists a critical value of weight coupling parameter𝛽βc,above which the density threshold of individuals is zero and below which the density threshold is larger than zero for WsF networks in the thermodynamic limit N→∞.Furthermore,the finite size scaling analysis show that for certain value𝛽β,the percolation transition of mobile individuals on a WsF network belongs to the same universality class of regular random graph percolation.

关键词： percolation cluster neighbor

simultaneous stabilization of Port-Hamiltonian systems subject to Actuation saturation and Input Delay

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International Journal of Automation and computing 2021年第5期18卷 849-854页

作者： Liang-cheng cai Department of Electrical Engineering Southwest Jiaotong UniversityEmei 614202China

This paper investigates the simultaneous stabilization of Port-Hamiltonian(PH) systems subject to actuation saturation(As) and input delay. Firstly, two parallel connecting PH systems subject to the As and input delay are proposed. secondly, a simultaneous stabilization control law is designed by a difference between the two feedback control laws containing the input ***, computing a Lyapunov-Krasovskii function assures the simultaneous stabilization of the above systems. Finally, simulation is given to show the correctness of the proposed contents.

关键词： Port-Hamiltonian system(PH) simultaneous stabilization actuator saturation input delay Lyapunov-Krasovskii function

cyclical Deformations of Quadrangles in s^(2)_(κ)and Defining Properties of Alexandrov spaces

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Acta Mathematica sinica,English series 2021年第4期37卷 597-640页

作者： Qing song cai colledge of science Tianjin University of TechnologyTianjin 300384P.R.China

This paper is mainly devoted to proving the four equivalent defining properties of a cBA(κ)*** proof is based on an interesting tool we established which describes the cyclical five-step deformation procedure for quadrangles in the model 2-plane s^(2)_(κ),including the limit shape of each *** a byproduct we give a complete list of cyclical deformation procedures for all kinds of quadrangles on *** last we make a contrast of geometric properties of cBA with cBB spaces,including a comparison between their defining properties and a discussion about Alexandrov’s Lemma.

关键词： spherical quadrangle Alexandrov spaces cBA spaces cBB spaces