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Evolution of the East China Sea sedimentary environment in the past 14 kyr: Insights from tetraethers-based proxies

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Science China Earth Sciences 2016年第5期59卷 927-938页

作者： GE Huangmin ZHANG ChuanLun VERSTEEGH Gerard j.m. CHEN LingLing FAN DaiDu DONG Liang LIU jingjing State Key Laboratory of marine Geology Tongji University Hadal Science and Technology Research Center (Shanghai Engineering Research Center of Hadal Science and Technology) Shanghai Ocean University Heisenberg Group on marine Kerogen Center for Marine Environmental Sciences (MARUM) Bremen University

We reconstruct the environmental evolution of the East China Sea in the past 14 kyr based on glycerol dialkyl glycerol tetraethers(GDGTs) in a sediment core from the subaqueous Yangtze River Delta. Two primary phases are recognized. Phase I(13.8–8 cal kyr BP) reflects a predominantly continental influence, showing distinctly higher concentrations of branched GDGTs(averaged 143 ng/g dry sediment weight, dsw) than isoprenoid GDGTs(averaged 36 ng/g dsw), high BIT index(branched vs. isoprenoid tetraethers) values(>0.78) and a fluctuating GDGT-0/crenarchaeol ratio(R_(0/5), varied from 0.52 to 3.81). Within this interval, temporal increases of terrestrial and marine influence are attributed to Younger Dryas(YD)(ca. 12.9–12.2 cal kyr BP) cold event and melt-water pulse(mWP)-1B(11.5–11.1 cal kyr BP), respectively. The prominent transition from 8 to 7.9 cal kyr BP shows a sharp decrease in BIT index value(marks the beginning of phase II. Afterwards, the proxies remain relatively constant, which indicates that phase II(7.9 cal kyr BP-present) is a shelf sedimentary environment with high stand of sea level. Overall, the BIT index in our record serves as a good marker for terrestrial influence at the site, and likely reflects the flooding history of the region. The TEX_(86)(Tetra Ether Index of tetraethers consisting of 86 carbons) proxy is not applicable in phase I because of an excess terrestrial influence; but it seems to be valid for revealing the annual SST in phase II(21.6±0.9°C, n=49). In contrast, the mBT'/CBT(methylation of Branched Tetraethers and Cyclization of Branched Tetraethers) proxy appears to faithfully record the annual mean air temperature(mAT)(14.3±0.63°C, n=68) and presents an integrated signal over the middle and lower Yangtze River drainage basin.

关键词： GDGTs Proxies Sedimentary environment evolution Holocene East China Sea

EIS STUDY ON ZINC RICH PAINTS IN 3.5% NaCl SOLUTION BY DOUBLE-CELL TEST

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Acta metallurgica Sinica(English Letters) 2002年第3期15卷 299-306页

作者： Dm. Xie, j.m. Hu, j.m. Wang and j.Q. ZhangDepartment of Chemistry, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory for Corrosion and Protection of metals, Institute of metal Research, The Chinese Academy of Sciences, Shenyang 110016, China Dept. of Chem. Zhejiang Univ. Hangzhou 310027 China

This paper discussed the possibility of obtaining electrochemical impedance spectroscopy (EIS) responses of zinc rich paints (ZRP) using serial double-cell (SDC). The influence of counter electrode was outlined. An equivalent circuit (ES) for the double-cell was then discussed. The relationship between EC, the time constant, the parameters in EC of SDC and those of two single sells was discussed. The results gained by serial double cell test are consistent with those of single cell test. It can be concluded that double cell test method can be used to study ZRP completely.

关键词： Electrodes Equivalent circuits Sodium chloride Spectroscopy Zinc

3-D FINITE ELEmENT ANALYSIS OF THE EFFECT OF WELDING RESIDUAL STRESS ON HYDROGEN DIFFUSION IN HYDROGEN CONTAINED ENVIRONmENT

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Acta metallurgica Sinica(English Letters) 2007年第5期20卷 347-354页

作者： W.C. jiang j.m. Gong j.Q. Tang H. Chen S.T. Tu College of mechanical and Power Engineering Nanjing University of Technology Nanjing 210009 China

The hydrogen distribution of 16mnR steel weldment in hydrogen contained environment was calculated using the finite element method （ FEm）. The effect of welding residual stress on hydrogen diffusion has been discussed using a 3-D sequential coupling finite element analysis procedure complied by Abaqus code. The hydrogen diffusion coefficient in weld metal, the heat affected zone （HAZ）, and the base metal of the 16mnR steel weldment were measured using the electrochemical permeation technique. The hydrogen diffusion without the effect of stress was also calculated and compared. Owing to the existence of welding residual stress, the hydrogen concentration was obviously increased and the hydrogen woum diffuse and accumulate in the higher stress region.

关键词： 16mnR steel hydrogen diffusion welding residual stress finite element analysis

Diurnal Variation of Southwest monsoon Rainfall at Indian Stations

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Advances in Atmospheric Sciences 1994年第1期11卷 111-120页

作者： j.m. Pathan(Indian Institute of Tropical meteorology, Pashan, Pune-411008, India) Indian Institute of Tropical meteorology Pashan Pune India

The paper presents the patterns of rainfall behavior brought out by the diagrams depicting the diurnal variation of SW monsoon rainfall at selected indian stations. The stations in different geographical locations are found to exhibit different patterns of diurnal variation of rainfall. In general, coastal and island stations show enhanced rainfall from midnight to morning hours and below average rainfall during day time. many inland stations show rainfall maximum towards afternoon/evening hours. Some hill stations show the same behavior as inland stations. However, at the heavy rainfall station of Cherrapunjee, the rainfall behavior is similar to that at the coastal stations. Possible physical mechanisms responsible for the diurnal variation of rainfall at stations under different categories, are briefly discussed. Harmonic analysis of hourly SW monsoon rainfall data of 33 stations show that for 19 stations, the first harmonic accounts for more than 50% of the variance of the rainfall series. These consist of (i) inland stations for which the maximum of the first harmonic is reached between 16 hours IST and midnight, and (n) coastal/island stations for which the maximum is seen between 03 and 07 hours IST. At most of the coastal and island stations, the first harmonic alone accounts for 75% orb more of the variance. For the heavy rainfall station of Cherrapunjee, the first harmonic which attains its maximum at 3.8 hours IST (-4.4 hours LT), is able to account for 96% of the variance of the rainfall series. It is hoped that the information contained in this paper about the pattern of diurnal modulation of monsoon rainfall may serve as background material to monsoon precipitation climatology.

关键词： Diurnal variation monsoon rainfall Indian stations Harmonic analysis Hourly rainfall

Ion shielding functional separator using halloysite containing a negative functional moiety for stability improvement of Li–S batteries

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journal of Energy Chemistry 2021年第9期30卷 334-340页

作者： Yong min Kwon jihoon Kim kuk Young Cho Sukeun Yoon Division of Advanced materials Engineering&Institute for Rare metals Kongju National UniversityChungnam 31080Republic of Korea Department of materials Science and Chemical Engineering Hanyang UniversityGyeonggi 15588Republic of Korea

Lithium–sulfur batteries are one of the attractive next-generation energy storage systems owing to theienvironmental friendliness,low cost,and high specific energy ***,the low electrical conductivity of sulfur,shuttling of soluble intermediate polysulfides between electrodes,and low capacitretention have hampered their commercial *** address these issues,we use a halloysitemodulated(H-m)separator in a lithium–sulfur battery to mitigate the shuttling *** H-m separator acts as a mutual Coulombic repulsion in lithium-sulfur batteries,thereby selectively permitting Lions and efficiently suppressing the transfer of undesired lithium polysulfides to the Li anode sidemoreover,the use of halloysite switches the surface of the separator from hydrophobic to hydrophilicconsequently improving the electrolyte wettability and adhesion between the separator and cathodeWhen sulfur-multi-walled carbon nanotube(S-mWCNT)composites are used as cathode active materialsa lithium–sulfur battery with an H-m separator exhibits first discharge and charge capacities of 1587 an1527 m Ah g-1,***,there is a consistent capacity retention up to 100 cyclesAccordingly,our approach demonstrates an economical and easily accessible strategy for commercialization of lithium–sulfur batteries.

关键词： Li–S batteries Halloysite Ion shielding Negative functional moiety Lithium polysulfides

NUmERICAL SImULATION OF PARTICLE SEPARATION IN AN OIL-SAND SEPARATOR

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journal of Hydrodynamics 2001年第1期13卷 81-85页

作者： Wei, X.L. Tian, W.D. Wang, j.m. Sheng, H.Z. Inst. of mechanics Chinese Acad. of Sci. Beijing 100080 China

The gathering systems of crude oil are greatly endangered by the fine sand and soil in oil. Up to now, how to separate sand from the viscid oil is still a technical problem for oil production at home or abroad. Recently, Institute of mechanics in Chinese Academy of Sciences has developed a new type of oil-sand separator, which has been applied successfully in oil field in situ. In this paper, the numerical method of vortex-stream function is used to predict the liquid-solid separating course and the efficiency for this oil-sand separator. Results show that the viscosity and particle diameter have much influence on the particle motion. The calculating separating efficiency is compared with that of experiment and indicates that this method can be used to model the complex two-phase flow in the separator.

关键词： Computer simulation Crude petroleum Petroleum engineering Separators

COmPOSITION TRIANGLE DIAGRAmS OF Ni-mn-Ga mAGNETIC SHAPE mEmORY ALLOYS

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Acta metallurgica Sinica(English Letters) 2006年第3期19卷 171-175页

作者： Y.F. Wang j.m. Wang C.B. jiang H.B. Xu School of materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

A statistical work has been done to collect the composition ranges of Ni-mn-Ga alloys exhibiting different structures and martensite start temperature （m,）, large magnetostrain or the co-existence of magnetic and structural transitions. The alloys with five-layered （5m）, seven-layered （7m） modulated and non-modulated （T） martensitic structures were mapped in the graph. An empirical formula has been presented to reflect the effect of elements nickel （Ni ）, manganese （ mn ） and gallium （Ga）, on the martensite start temperature （m3）. The martensitic structure is sensitive to the composition and the martensitic transformation temperature is most drastically affected by the Ni content. The alloys with large magnetostrain or co-existence effect of the magnetic and structural transitions were also listed in a limited area.

关键词： Ni2mnGa alloy martensitic transformation magnetic shape memory alloy

Two-neutron transfer reactions as a tool to study the interplay between shape coexistence and quantum phase transitions

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Chinese Physics C 2020年第12期44卷 103-113页

作者： j.E.García-Ramos j.m.Arias A.Vitturi Departamento de Ciencias Integradas y Centro de Estudios Avanzados en Física Matemática y ComputaciónUniversidad de Huelva21071 HuelvaSpain Instituto Carlos I de Física Teórica y Computacional Universidad de GranadaFuentenueva s/n18071 GranadaSpain Departamento de Física Atómica Molecular y NuclearUniversidad de SevillaApdo.106541080 SevillaSpain Dipartimento di Fisica e Astronomia“Galileo Galilei” Universitádegli Studi di PadovaPadovaItaly

The atomic mass table presents zones where the structure of the states changes rapidly as a function of the neutron or proton *** them,notable examples are the A≈100 Zr region,the Pb region around the neutron midshell(N=104),and the N≈90 rare-earth *** observed phenomena can be understood in terms of either shape coexistence or quantum phase *** objective of this study is to find an observable that can distinguish between both shape coexistence and quantum phase *** an observable to be analyzed,we selected the two-neutron transfer intensity between the 0+states in the parent and daughter *** framework used for this study is the Interacting Boson model(IBm),including its version with configuration mixing(IBm-Cm).To generate wave functions of isotope chains of interest needed for calculating transfer intensities,previous systematic studies using IBm and IBm-Cm were used without changing the *** results of two-neutron transfer intensities are presented for Zr,Hg,and Pt isotopic chains using ***,for Zr,Pt,and Sm isotopic chains,the results are presented using IBm with only a single configuration,i.e.,without using configuration *** Zr,the two-neutron transfer intensities between the ground states provide a clear observable,indicating that normal and intruder configurations coexist in the low-lying spectrum and cross at A=98→*** can help clarify whether shape coexistence induces a given quantum phase *** Pt,in which shape coexistence is present and the regular and intruder configurations cross for the ground state,there is almost no impact on the value of the two-neutron transfer *** is the situation with Hg,where the ground state always has a regular *** the Sm isotope chain,which is one of the quantum phase transition paradigms,the value of the two-neutron transfer intensity is affected strongly.

关键词： two nucleon transfer reactions shape coexistence quantum phase transition interacting boson model

Prussian blue and its analogues as advanced supercapacitor electrodes

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journal of Energy Chemistry 2020年第11期29卷 206-229页

作者： Emad S.Goda Seungho Lee muhammad Sohail kuk Ro Yoon Organic Nanomarerials Lab Department of ChemistryHannam UniversityDaejeon 34054Republic of Korea Department of Chemistry Hannam UniversityDaejeon 34054Republic of Korea Fire Protection Laboratory National Institute of Standards136.Giza 12211Egypt Advanced Energy and System Engineering University of Science and TechnologyDaejeon 34113Republic of Korea

Remarkable attention has been directed to Prussian blue(PB) and its analogues(PBA) as one of the most widely used metal-organic frameworks(mOFs) especially in the field of energy storage devices due to their fabulous features such as 3D open framework, high surface area, controllable distribution of pores and the low cost. Nevertheless, their depressed conductivity causes some insulation when being used as an electrode for supercapacitors leading to be restricted in further applications particularly the electronics. To the best of our knowledge, our review aimed primarily to give a total picture of the research that was done on utilizing PB and PBA for fabricating the electrodes of supercapacitor, studying their synthesis approaches in addition to the hybridization with other materials such as graphene, CNTs and conducting polymer. It also addresses the transformation of PB or PBA into other interesting nanostructures such as oxides, sulfides, and bicomponent of graphitic carbon nitride/metal oxides, as well. Furthermore,It exhibits various avenues for overcoming their disadvantages of bad cycle life, retention rate and not achieving the desired values of energy/power densities opening the door for enlarging the number of researches on their application as supercapacitors.

关键词： metal hexacyanoferrates Supercapacitors Electrolyte Energy density Cyclic stability