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Modification of pore size in activated carbon by benzene deposition and its effects on ch4/n2 separation

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Journal of Coal Science & Engineering(ch.na) 2011年第4期17卷 418-421页

作者： ZHAnG Jin-hua chE Yong-fang li Lan-ting BAO Peng-ch.ng State Key Laboratory of Coal Mining and Environment Protection （ch.na Coal Research Institute） Beijing 100013 China Technical Institute of Physics and chemistry Chinese Academy of Sciences Beijing 100190 China

Anthracite coal was used as raw material to prepare activated carbons as the carbon support in the carbonization-activation process. Modification of the pore size of the activated carbon by chemical vapor deposition of carbon from benzene was examined. These samples were characterized by adsorption of n2 at 77 K and ch4 and n2 at 303 K. The microporosity of these samples was evaluated by the Dubinin-Astakhov Equation. The pore size distribution was obtained by the DFT method applied to the n2 adsorption data at 77 K. The separation selectivity was obtained by the Langmuir Equation. The surface morphology was characterized by an environmental scanning electron microscope. It was observed that all samples of carbon molecular sieves studied were microporous carbonaceous materials. CMS-2 prepared in the present study has a better n2/ch4 separation performance; it can satisfy the requirements of the pressure swing adsorption for concentrating ch4 from the n2/ch4 mixture gas.

关键词： benzene deposition carbon molecular sieves adsorption property

Phase Evolution during the Sintering of Submicron Ti(C,n)-Based Cermets

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Rare Metals 2001年第4期20卷 248-254页

作者： li, ch Xiong, WH Yu, LX Huazhong Univ Sci & Technol State Key Lab Plast Forming Simulat & Die & Mould Wuhan 430074 Peoples R China

The submicron powder mixtures of TiC-Tin-WC-Mo-C-ni sintered at 1400degreesC or below in vacuum were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. The results showed that Mo2C formed at 800degreesC or below. Both WC and Mo2C disappeared at 1200degreesC, and Tin disappeared at 1250degreesC. In addition, the variations of lattice constants of the titanium carbonitride and nickel binder phase with sintering temperature were experimentally obtained, and the reason was analyzed.

关键词： submicron cermet phase sintering

Estimating rock properties using sound signal dominant frequencies during diamond core drilling operations

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Journal of Rock Mech.nics and Geotechnical Engineering 2019年第4期11卷 850-859页

作者： ch.Vijaya Kumar Harsha Vardhan ch.S.n.Murthy n.C.Karmakar Department of Mining Engineering National Institute of Technology KarnatakaSurathkalIndia Indian Institute of Technology (BHU) VaranasiIndia

In many engineering applications such as mining,geotechnical and petroleum industries,drilling operation is widely *** drilling operation produces sound by-product,which could be helpful for preliminary estimation of the rock ***,determination of rock properties is very difficult by the conventional methods in terms of high accuracy,and thus it is expensive and *** this context,a new technique was developed based on the estimation of rock properties using dominant frequencies from sound pressure level generated during diamond core drilling ***,sound pressure level was recorded and sound signals of these sound frequencies were analyzed using fast Fourier transform (FFT).Rock drilling experiments were performed on five different types of rock samples using computer numerical control (CnC) drilling mach.ne BMV 45 *** simple linear regression analysis,mathematical equations were developed for various rock properties,*** compressive strength,Brazilian tensile strength,density,and dominant frequencies of sound pressure *** developed models can be utilized at early stage of design to predict rock properties.

关键词： Rock properties Sound pressure level Fast Fourier transform (FFT) Sound signal Core drilling Dominant frequencies

Effect of Potassium Addition on Coprecipitated Iron Catalysts for Fischer-Tropsch Synthesis Using Bio-oil-syngas

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ch.nese Journal of chemical Physics 2008年第2期21卷 141-150页

作者： Zhao-xiang Wang ting Dong Tao Kan Quan-xin li Department of chemical Physics Lab of Biomass Clean Energy University of Science and Technology of China Hefei 230026 China

The effects of potassium addition and the potassium content on the activity and selectivity of coprecipitated iron catalyst for Fischer-Tropsch synthesis （FTS） were studied in a fixed bed reactor at 1.5 MPa, 300 ℃, and contact time （W/F） of 12.5 gcath/mol using the model bio-oil-syngas of H2/CO/CO2/n2 （62/8/25/5, vol%）. It was found that potassium addition increases the catalyst activity for FTS and the reverse water gas shift reaction. Moreover, potassium increases the average molecular weight （chain length） of the hydrocarbon products. With the increase of potassium content, it was found that ch4 selectivity decreases and the selectivity of liquid phase products （C5＋） increases. The characteristics of FTS catalysts with different potassium content were also investigated by various characterization measurements including X-ray diffraction, X-ray photoelectron spectroscopy and Brunauer-Emmett-Teller surface area. Based on experimental results, 100Fe/6Cu/16Al/6K （weight ratio） was selected as the optimal catalyst for FTS from bio-oil-syngas. The results indicate that the 100Fe/6Cu/16Al/6K catalyst is one of the most promising candidates to directly synthesize liquid bio-fuel using bio-oil-syngas.

关键词： Bio-oil-syngas Fischer-Tropsch synthesis Potassium Coprecipitated iron

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HchO driven by photoelectrocatalysis

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Journal of Energy chemistry 2025年第1期100卷 39-49页

作者： Hongqiang Yang Jianfeng Zheng Guoyu Wang Yifei Gao Yatao Yang Jia li Xiaojin Han Yan Cui Zhanggen Huang national Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of ch.nese Academy of Science Shenyang University of chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3n4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HchO were absorbed at Zn site and n site,***,*CO generated from CO2and HchO was converted to*ch3O and*chO on the dual-active-site *** detailed reaction mech.nism experiments indicated that C–C coupling only occurred between*CO and*ch3O in electrocatalysis *** from the“*CO+*ch3O”path,another“*CO+*chO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HchO simultaneously driven by light and electricity.

关键词： Ethanol

Phosphine/Benzocyclone-based neutral nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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ch.nese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang li Pan Vladislav A.Tuskaev Svetlana ch.Gagieva Yue-Sheng li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A n nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(ni1: Ar = Ph;ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes ni2 and ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

Can a dam type of an alpine lake be derived from lake geometry?A negative result

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Journal of Mountain Science 2021年第3期18卷 614-621页

作者： Adam EMMER Vojtěch CURIn University of Graz Institute of Geography and Regional ScienceCascade|The Mountain Processes and Mountain Hazards GroupGraz 8010Austria Czech Academy of Sciences Prague 16500Czechia Global ch.nge Research Institute Czech University of Life Sciences PragueFaculty of Environmental SciencesBrno 60300Czechia

Glacial lake outburst floods(GLOFs)represent one of the most serious hazard and risk in deglaciating high mountain regions worldwide and the need for GLOF hazard and risk assessment is *** a consequence,numerous region-and nation-wide GLOF assessment studies have been published *** studies cover large areas and consider hundreds to thousands of lakes,prioritizing the hazard posed by ***,certain simplification is required for executing such studies,often resulting in neglecting qualitative characteristics which would need manual *** lake dam types(e.g.,bedrock-dammed,moraine-dammed)are often not distinguished,despite they control GLOF mech.nism(dam overtopping/dam breach)and thus GLOF *** this study,we explore the potential of easily measurable quantitative characteristics and four ratios to approximate the lake dam *** dataset of 851 lakes of the Cordillera Blanca suggests that while variances and means of these characteristics of individual lake types differ significantly(F-test,t-test),value distribution of different geometrical properties can’t be used for the originally proposed purpose along the *** only promising results are obtained for extreme values(selected bins)of the *** instance,the low width to length ratio indicates likely morainedammed lake while the high value of ratio indicating round-shape of the lake indicates increased likelihood of bedrock-dammed ***,we report a negative result of our experiment since there are negligible differences of relative frequencies in most of the bins along the spectra.

关键词： Alpine lake High mountain lake GLOFs Glacial lake Moraine-dammed Bedrock-dammed negative result Cordillera Blanca

nonstationary fuzzy forecasting of wind and wave climate in very long-term scales

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Journal of Ocean Engineering and Science 2018年第2期3卷 144-155页

作者： ch.n.Stefanakos E.Vanem SInTEF Ocean Department of Energy and TransportPostboks 4762 TorgardenTrondheim NO-7465Norway DnV GL Group Technology and ResearchP.O Box 3001322HøvikNorway

Global climate ch.nge may have serious impact on human activities in coastal and other *** ch.nge may affect the degree of storminess and,hence,ch.nge the wind-driven ocean wave *** may affect the risks associated with maritime activities such as shipping and offshore oil and ***,there is a recognized need to understand better how climate ch.nge will affect such ***,such understanding comes from future projections of the wind and wave climate from numerical climate models and from the stochastic modelling of such *** work investigates the applicability of a recently proposed nonstationary fuzzy modelling to wind and wave climatic *** to this,fuzzy inference models(FIS)are coupled with nonstationary time series modelling,providing us with less biased climatic *** long-term datasets for an area in the north Atlantic Ocean are used in the present study,namely nORA10(57 years)and ExWaCli(30 years in the present and 30 years in the future).Two distinct experiments have been performed to simulate future values of the time series in a climatic *** assessment of the simulations by means of the actual values kept for comparison purposes gives very good results.

关键词： Fuzzy time series Wind and wave data Forecasting nonstationary Ocean wind and wave climate

CO_2/ch_4 and ch_4/n_2 separation on isomeric metal organic frameworks

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ch.nese Journal of chemical Engineering 2016年第12期24卷 1687-1694页

作者： Xiaoqing Wang libo li Jiangfeng Yang Jinping li Research Institute of special chemicals Taiyuan University of Technology Taiyuan 030024 China

Two isomeric metal-organic frameworks(MOFs) with 2-dimensional(2D) and 3-dimensional(3D) topologies both comprised of Cu(Ⅱ) and OTf(OTf = trifluoromethanesulfonate) ions were synthesized and *** CO_2,ch_4 and n_2 adsorption properties of the two isomeric MOFs were investigated from 263 K to 298 K at0.1 *** results showed that the 2D MOF exhibited a higher selectivity for CO_2 from CO_2/ch_4 and ch_4from ch_4/n_2 compared to the 3D MOF,even though it possessed a lower surface area and pore *** higher adsorption heats of gases on the 2D MOF inferred the strong adsorption potential energy in the layered *** separation experiments using CO_2/ch_4 and ch_4/n_2 mixtures on the two MOFs proved that the2 D MOF had a longer elution time than the 3D MOF as well as better separation abilities.

关键词： Metal–organic frameworks Isomeric frameworks Adsorption Separation