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Acta Geologica Sinica(English Edition) 2014年第1期88卷 213-225页

作者： Durbar RAY Dalayya KOTA Pranab DAS L.Surya Prakash V.D.KHEDEKAR Anil L.PAROPKARI Abhay V.MUDHOLKAR CSIR-National institute of Oceanography Indian School of Mines

An extinct hydrothermal barite-silica chimney from the Franklin Seamount of the Woodlark Basin, in the southwestern Pacific Ocean, was investigated for mineral distribution and geochemical composition. Six layers on either side of the orifice of a chimney show significant disparity in color, mineral assemblage and major element composition. Electron microscope（SEM） images reveal that the peripheral wall of the chimney is composed of colloform silica, suggesting that incipient precipitation of silica-saturated hydrothermal fluid initiated the development of the chimney wall. Intermediate layers, between the exterior wall and the inner fluid-orifice, dominate with barite and sulfides. Low Sr-to-Ba ratios（SrO/BaO = 0.015–0.017） indicate restricted fluid-seawater mixing, which causes relatively high-temperature formation of the intermediate layers. Whereas the innermost layer bordering the chimney orifice is characterized by more silica and a higher Sr-to-Ba ratio（SrO/BaO = 0.023）, could have formed due to a paragenetic shift from a high-temperature active phase to a cooler waning stage of formation. A paragenetic shift is also probably responsible for the change in mineral formation mechanism that resulted in the textural variation of barite and colloform silica developed during different growth phases of this barite-silica chimney.

关键词： mineralogy oceanography geochemistry Franklin seamount barite-silica chimney

Physicochemical and Thermal Properties of Some Key Tropical Sawdust Woods for Energy Production

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Journal of Sustainable Bioenergy Systems 2024年第1期14卷 1-22页

作者： Davy Fiwa Kaoke Yann Le Brech Emmanuel Talla Anthony Dufour Patrick Mountapmbeme Kouotou Department of Chemical Engineering School of Chemical Engineering and Mineral Industries University of Ngaoundere Ngaoundere Cameroon National Advanced School of Engineering of Maroua University of Maroua Maroua Cameroon Laboratory of Reactions and Process Engineering University of Lorraine-France Nancy France Higher institute of Agriculture Wood Water and Environment University of Ebolowa Ebolowa Cameroon

In South Saharan countries, 85% of the population uses biomass as a primary energy source. Cameroon presents one of the highest biomass energy and sawmills produce important sawdust resources which are not used and are burnt in piles leading to significant air toxic emissions. Therefore, we have to valorize industrially these available sawdusts. This study focuses on the physicochemical and thermochemical analysis of Ayous, Sapelli and Tali sawdust. The proximate and ultimate analysis, particle size, structural composition, as well as heavy metal content and calorific value were determined. In addition, the thermogravimetric mass losses were also estimated. The results showed that high water contents (24% - 41%) were recorded in the raw sawdust, and the thermal treatment reduced these contents from 78% to values in the range of 4% - 9%. The values for ash and volatile matter content were respectively between 0.25% - 0.74% and 68% - 76%. The LHV is higher in Ayous (17.5 MJ/kg) and Sapelli (16.8 MJ/kg) than that of Tali (15.7 MJ/kg). The concentration of heavy metals is very low in each species. Extractives are more present in Tali (16.06%) than in the other sawdusts. Pyrolysis of sawdust shows the typical decomposition of hemicellulose (270˚C - 325˚C), cellulose (325˚C - 400˚C) and lignin (200˚C - 550˚C) with a maximum loss of 75% at 370˚C and the melting point is 320˚C. The results of the sawdust parameters determined in the paper can be valorized to reduce pollutants emissions by developing the efficiency and effectiveness of biomass energy processes and promoting the use of biomass as a sustainable alternative to traditional fossil fuels.

关键词： Wood Sawmills Sawdust Combustion Energy

Melt Inclusions in Basalts of Ross Island Area,Antarctica

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Acta Geochimica 1988年第1期7卷 46-56页

作者：毛冬青卢焕章方根保 Academia Sinica institute of Geochemistry institute of Gold Research Shenyang

There are many melt and fluid inclusions（mainly CO;-rich）in olivine and pyroxene phenocrysts inbasalts from the Ross Island *** melt inclusions can be classified as follows:（1）crystalline meltinclusions（type Ⅰ）,（2）fluid-melt inclusions（type Ⅱ）and（3）glass inclusions （type Ⅲ）.The daughter mineralsin type I inchide olivine,plagioclase,ilmenite,***-melt inclusions are a new type which represent theimmiscibility of magma and fluid at a particular stage of *** types of fluid-melt inclusions wereexamined in this study:a)crystal+liquid+gas,b)inclusions coexisting with glass inclusions and fluidinclusions,and c)crystal+daughter mineral（dissolved salt）+*** primary and secondary meltinclusions are recognizable in the *** secondary melt inclusions were formed during healing offractures in the host minerals in the process of magma *** homogenization temperatures（both Leitz 1350 stage and quench method were used）of meltinclusions in hasalts range from 1190 to 1350℃ at high pressure（about 7 kbars）,indicating that the basaltsmay have come from the upper ***-fluid immiscibility in basaltic magma shows that the CO;-riehfluids may be the main fluid phase in the upper mantle,which are of significance in understanding theevolution of magma and various processes in the deep levels of the *** homogenization temperatures of melt and aqueous fluid inclusions in granites and metamorphicrocks in this area vary from 980 to 1100℃ and 279 to 350℃,respectively.

关键词： Melt Inclusions in Basalts of Ross Island Area,Antarctica

Fabricating high-performance sodium ion capacitors with P2-Na_(0.67)Co_(0.5)Mn_(0.5)O_2 and MOF-derived carbon

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Journal of Energy Chemistry 2019年第1期28卷 79-84页

作者： Haichen Gu Lingjun Kong Huijuan Cui Xianlong Zhou Zhaojun Xie Zhen Zhou School of Materials Science and Engineering National Institute for Advanced Materials Institute of New Energy Material Chemistry Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Nankai University

Sodium ion capacitors(SICs) have been considered as a kind of promising devices to achieve both high power and energy density. However, it is still a challenge to achieve high energy output at elevated power delivery due to the poor rate capability of battery-type electrode materials and the kinetic mismatch with capacitor-type electrode materials. In this work, to fabricate SICs, P2-Na_(0.67)Co_(0.5)Mn_(0.5)O_2(P2-NCM)was chosen as the battery-type cathode material, and a typical metal-organic framework(MOF) material,zeolitic imidazolate framework-8(ZIF-8) derived carbon(ZDC) was utilized as the capacitor-type anode material. Due to the kinetic match and high-rate performance of both electrodes, the ZDC//P2-NCM SICs exhibited an energy output of 18.8 Wh kg^(-1) at a high power delivery of 12.75 kW kg^(-1).

关键词： Energy density Power density P2-phase material Zeolitic imidazolate framework-8 Sodium ion capacitors

Application of particle trajectory model in 1D planar ejection

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Journal of Central South University 2008年第S1期15卷 149-154页

作者：刘坤柏劲松李平 institute of Fluid Physics Chinese Academy of Engineering Physics

A simple one-dimensional planar model for ejection was set up based on *** numerical simulation was performed on this model with particle trajectory model *** Eulerian finite volume method was conducted to resolve gas *** Lagrangian method was imposed to track each *** interaction between gas and particles was responded as source terms in governing equations which were induced by *** effects of total spraying mass,particle size and other factors on the mixture of particles and gas were *** spatial distributions of particle mass and velocity at different time were *** result shows that the numerical results are qualitatively consistent to those of experiments.

关键词： ejection particle mixture one-dimensional planar ejection model particle trajectory model particles spatial distributions

Electrochemical and structural performances of Li[Ni_(0.133)Li_(0.2)Co_(0.133)Mn_(0.533)]O_(2)material during different cycle potential windows

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Rare Metals 2022年第8期41卷 2664-2679页

作者： Jun-Qiang Li Yun-Jie Yang Jing Pang Research and Development Center for Vehicle Battery and Energy Storage General Research Institute for Nonferrous MetalsBeijing100088China Beijing institute of Chemical Reagents Beijing102607China

The effects of cycle potential window on electrochemical behaviors,structural characteristics,and surface changes in Li[Ni_(0.133)Li_(0.2)Co_(0.133)Mn_(0.533)]O_(2)(or 0.5 Li_(2)MnO_(3)·0.5 Li(Co_(0.333)Ni_(0.333)Mn_(0.333))O2)in lithium-ion battery were *** flat charge potential plateaus,~3.9 and~4.5 V,are observed in the initial charge curves of the *** changes in specific capacity and columbic efficiency are presented at~4.5 V during the first *** specific peaks show an obvious shift with the increase in charge cutoff *** the charge cutoff potential is above4.4 V,the cycle performance decreases with the increase in charge cutoff potentials.A film with the composition of C and O elements is observed on the cycled composite particle.

关键词： Lithium-ion battery Li-rich solid solution material Charge cutoff potential Cycle potential window Cycle performance

Courant-Snyder invariant density screening method for emittance analysis

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Chinese Physics C 2011年第11期35卷 1059-1065页

作者：孙纪磊唐靖宇敬罕涛 institute of High Energy Physics Chinese Academy of Sciences

Emittance is an important characteristic of describing charged particle beams. In hadron accelerators, we often meet irregular beam distributions that are not appropriately described by a single rms emittance or 95% emittance or total emittance. In this paper, it is pointed out that in many cases a beam halo should be described with very different Courant-Snyder parameters from the ones used for the beam core. A new method - the Courant-Snyder invariant density screening method - is introduced for analyzing emittance data clearly and accurately. The method treats the emittance data from both measurements and numerical simulations. The method uses the statistical distribution of the beam around each particle in phase space to mark its local density parameter, and then uses the density distribution to calculate the beam parameters such as the Courant-Snyder parameters and emittance for different beam boundary definitions. The method has been used in the calculations for beams from different sources, and shows its advantages over other methods. An application code based on the method including the graphic interface has also been designed.

关键词： emittance Courant-Snyder invariant density Courant-Snyder parameters beam halo

Theoretical and experimental investigations of coherent phonon dynamics in sapphire crystal using femto-second time-resolved coherent anti-Stokes Raman scattering

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Chinese Physics B 2011年第12期20卷 315-321页

作者：杜鑫张明福何兴孟庆琨宋云飞杨延强韩杰才 Centre for Condensed Matter Science and Technology Department of PhysicsHarbin Institute of Technology College of Foundation Science Harbin University of Commerce Centre for Composite Materials Harbin Institute of Technology

We report on the theoretical and the experimental investigations of the coherent phonon dynamics in sapphire crystal using the femtosecond time-resolved coherent anti-Stokes Raman scattering （fs-CARS） technique. The temporal chirped white-light continuum （WLC） is used for the Stokes pulse, therefore we can perform the selective excitation of the phonon modes without using a complicated laser system. The expected quantum beat phenomenon is clearly observed. The theoretical formulas consist very well with the experimental results. The dephasing times of the excited phonon modes, the wavenumber difference, and the phase shift between the simultaneously excited modes are obtained and discussed. This work opens up a way to study directly high-frequency coherent phonon dynamics in bulk crystals on a femtosecond time scale and is especially helpful for understanding the nature of coherent phonons.

关键词： coherent phonon femtosecond time-resolved coherent anti-Stokes Raman scattering dephasing quantum beat

All-Digital Self-Interference Cancellation in Zero-IF Full-Duplex Transceivers

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China Communications 2016年第11期13卷 27-34页

作者： Lu Tian Shuai Wang Zhiheng Cheng Xiangyuan Bu School of Information Science and Electronics Beijing Institute of Technology

In this paper,a general scheme in digital self-interference cancellation at baseband for zero-IF full-duplex transceivers is presented. We model the self-interference signals specifically with only the nonlinear distortion signals falling in receiving band considered. A joint estimation algorithm is proposed for compensating the time delay and frequency offset taking into account the IQ amplitude and phase imbalances from mixers. The memory effect and nonlinear distortion are adaptively estimated by the de-correlated normalized least mean square(DNLMS) algorithm. Numerical simulation results demonstrate that the proposed self-interference cancellation scheme can efficiently compensate the self-interference and outperform the existing traditional solutions.

关键词： communication systems full-duplex transceivers self-interference cancellation IQ imbalance de-correlated normalized least mean square algorithm

Friction and Wear Properties of TiAl and Ti_2AlN/TiAl Composites at High Temperature

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Journal of Wuhan University of Technology(Materials Science) 2013年第5期28卷 1023-1028页

作者：孙东立 SUN Tao WANG Qing HAN Xiuli GUO Linlin School of Materials Science and Engineering Harbin Institute of Technology

The high-temperature friction and wear properties of TiAl alloys and Ti2AlN/TiAl composites （TTC） in contact with nickel-based superalloy were studied. The results showed that, at 800 and 1 000 ℃, the coefficient of the friction （COF） decreased with the increase of sliding velocity and the wear loss of the TTC decreased with the increase of volume fraction of Ti2AlN. The wear mechanisms of the pairs are adhesive wear and the wear debris mainly comes from the contacting nickel-based superalloy. The intergranular fracture and the cracking of the phase boundary in the lamellar structure are the wear mode of TiAl alloy. The wear mode of TTC is phase boundary fracture and adhesive spalling. The abrasive resistance of TTC is slightly higher than that of TiAl alloy.

关键词： TiA1 alloy Ti2A1N/TiA1 composites friction and wear at high-temperaturer