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STUDY ON ThE PROPERTIES OF DIFFERENT ACTIVATED CARBON FIBERS AND ThEIR ADSORPTION ChARACTERISTICS FOR FORMALDEhYDE

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 467-472页

作者： h.q. Rong, Z.Y. Ryu and J.T. Zheng (Institute of Coal Chemistry, The Chinese Academy of Sciences, P.O.Box 165, Taiyuan 030001, China) Institute of Coal Chemistry The Chinese Academy of Sciences

Porous structure and surface chemistry of activated carbon fibers obtained by differ-ent precursors and activation methods were investigated. Adsorption isotherms werecharacterized by nitrogen adsorption at 77K over a relative pressure range from 10 6to 1. The regularization method according to Density Functional Theory (DFT) wasemployed to calculate the pore size distribution in the samples. Their specific surfaceareas were calculated by BET method, micropore volume and microporous specificsurface area calculated by t-plot method and MPD by horvath-Kawazoe equation. Mi-cropore volume of rayon-based ACF was higher than that of other samples. The staticand dynamic adsorption capacity for formaldehyde on different ACFs was *** results show that steam activated Rayon-based A CFs had higher adsorption capac-ity than that of steam and KOh activated PAN-A CFs. Breakthrough curves illustratedthat Rayon-ACFs had longer breakthrough time, thus they possessed higher adsorp-tion capacity for formaldehyde than that of PAN-ACFs. The entire sample had smalladsorption capacity and short breakthrough time for water. Rayon-A CFs had exccl-lent adsorption selectivity for formaldehyde than PAN-ACFs. And the samples withhigh surface areas had relatively high adsorption capacity for formaldehyde. Elementaicontent of different A CFs were performed. Rayon-based A CFs contained more oxygenthan PAN-ACFs, which may be attributed to their excellent adsorption capacity forformaldehyde.

关键词： activated carbon fiber porous structure surface chemistry formaldehyde adsorption characteristic

Chemical, carbon and sulfur isotopic compositions constrain the origin of Upper Carboniferous-Lower Triassic gases in eastern Sichuan Basin, SW China

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Science China Earth Sciences 2024年第10期67卷 3169-3185页

作者： Chunfang CAI Ilya KUTUZOV Wenhua MEI Daowei wang Bing LUO Shipeng hUANG Bing hE Alon AMRANI China University of Petroleum National Key Lab Petroleum Resource&EngineeringBeijing 102249China State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institute of Earth Sciences The Hebrew UniversityJerusalem 91904Israel College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Yulin University Yulin 719000China Research Institute of Exploration and Development Southwest Oil&Gas Field CompanyPetroChinaChengdu 610051China PetroChina Research Institute of Petroleum Exploration and DevelopmentBeijing 100083China

Methane dominated gas is one of the cleanest energy resources;however, there is no direct method to determine its source rock. Natural gases produced from the eastern Sichuan Basin together with seismic data were studied for their sources and secondary alteration by thermochemical sulfate reduction(TSR). Our results demonstrate that Upper Permian to Lower Triassic(P_(3)ch-T_(1)f) gases in the surrounding of the Kaijiang-Liangping area show volatile organic sulfur compounds(VOSCs) δ^(34)S values close to those of the associated h_(2)S, and may have been altered by methane-dominated TSR, resulting in positive shift in methane δ^(13)C_(1)values with increasing TSR extents. Other(or group 2) gases produced from the P_(3)ch-T_(1)f reservoirs from the southern area and the Upper Carboniferous to Middle Permian(C_(2)h-P_(2)q) from the eastern Sichuan Basin are not significantly changed by TSR, show similar δ^(34)S values between the kerogens and some VOSCs, and may have been derived from the Lower Silurian and Middle Permian source rocks. This study demonstrates a case for the first time showing the δ^(34)S values of VOSCs can be used as a tool for direct correlation between non-TSR altered gas and source rocks. Methane-dominated gas pools can be found using gas and source rock geochemistry combined with seismic data.

关键词： Sulfur isotopes Volatile organic sulfur compounds Thermochemical sulfate reduction Sichuan Basin Gas-source rock correlation

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Analytical and numerical studies for seiches in a closed basin with various geometric shapes of longitudinal section

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Theoretical & Applied Mechanics Letters 2021年第3期11卷 151-156页

作者： I.Magdalena N.Karima h.q.Rif’atin Faculty of Mathematics and Natural Sciences Bandung Institute of TechnologyBandungIndonesia

Seiches are long-period standing waves with a unique period called a natural resonant period,during which the phenomenon of resonance *** occurrence of resonance in coastal areas can cause destruction to surrounding natural and man-made *** determining the resonant period of a given basin,we can pinpoint the conditions that allow waves to achieve *** this study,a mathematical model is developed from the shallow water equations to examine seiches and resonances in various types of closed *** developed model is solved analytically using the separation of variables method to determine the seiches’fundamental resonant *** between the analytical solutions and experimental measurements for resonant periods are also *** is shown that the analytical resonant period confirms the experimental data for closed basin of various geometric *** a finite volume method on a staggered grid,the model is solved numerically to simulate the wave profile when resonance phenomenon *** those numerical simulations,we also obtain the fundamental resonant period for each basin which agrees with the derived analytical period.

关键词： Seiches Fundamental resonant period Closed basin Shallow water equations Finite volume method

ThE PREPARATION AND ChARACTERISTICS STUDY OF TiN_xO_y SPECTRAL SELECTIVE ABSORBING FILM BY MAGNETRON SPUTTERING

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 385-388页

作者： D.Chen h.Shen B.W.wang h.q.wang MaterialandScienceEngineeringInstitute SouthChinaUniversityofTechnologyGuangzhou510641China EnergyEngineeringInstitute ZhongshanUniversityGuangzhou510275China／／GuangzhouInstituteofEnergyConversionTheChineseAcademyofSciencesGuangzhou510640China GuangzhouInstituteofEnergyConversion TheChineseAcademyofSciencesGuangzhou510640China SchoolofMechanismandAutomobile ShenyangInstituteofAeronauticalEngineeringShenyang110034China

Spectral selective absorbent film is a crucial factor for the solar heating devi ce. There are many kinds of spectral selective absorbing film made by different ways. TiNxOy thin film with excellent spectral selecting absobent property were successfully prepared by DC magnetron sputtering with Ar as working gas, N2 and O2 as reactive gas, 99.9% titanium as the target and is copper slice as the subs trate. In this article, the optical characteristics and microstructure of TiNxO y thin film were studied. Inputing O2 can decrease the reflection of the visible lights, and double layer film can get good absorption for solar energy.

关键词： spectrum selecting absorbent film TiNxOy magnetron sputtering

Experimental Study and Numerical Simulation of the Casting-Forging Complex Near Net Forming of Alternator Claw-pole

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上海交通大学学报 2004年第z2期38卷 79-82页

作者： J.L.Song D.J.hu q.C.wang h.q.Chen h.G.Guo School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China

As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.

关键词： alternator claw-pole casting-forging near net forming numerical simulation

Crack Initiation Mechanism of Z3CN20.09M Duplex Stainless Steel during Corrosion Fatigue in Water and Air at 290 °C

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Journal of Materials Science & Technology 2015年第11期31卷 1144-1150页

作者： h.C.Wu B.Yang Y.Z.Shi q.Gao Y.q.wang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Collaborative Innovation Center of Universal Iron & Steel Technology School of Materials Science and Engineering Anhui University of Technology

The crack initiation mechanism of a Z3CN20.09M duplex stainless steel （DSS） during corrosion fatigue （CF） in water and air at 290 ℃ was investigated by using a CF cracking machine and a scanning electron microscopy （SEM）. The cracks were initiated successively at the persistent stip bands （PSBs）, phase boundaries （PBs） and pitting corrosion points （PCPs） of the specimens when they were tested in water at 290 ℃, while in airat 290 ℃ the cracks were only initiated at the PSBs and PBs. And the cracks were found mainly to initiate at the PSBs and PBs when the specimens were tested in water and air at 290 ℃, respectively. The results also reveal that the cracks were likely to be initiated at the first 20% of fatigue life of the specimens tested in water at 290 ℃. however, the cracks were not found until 50% of fatigue life when tested in air at 290 ℃. Moreover, the crack numbers of the specimens tested in water at 290 ℃ were much more than those tested in air at 290 ℃.

关键词： Duplex stainless steel Corrosion fatigue Crack initiation high temperature water

Influence of Fe Addition on Products of Self-Propagating high-Temperature Synthesis Reaction in 3Ti-Si-2C System

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稀有金属材料与工程 2009年第A3期38卷 113-118页

作者： Guan q L wang h Y Li S L Si W P Jiang q C Key Laboratory of Automobile Materials of Ministry of Education Jilin University Changchun 130025 China

Influence of Fe addition on products of self-propagating high-temperature synthesis (ShS) reaction in 3Ti-Si-2C system was investigated in the present study. Without Fe addition, Ti5Si3 and TiC are the dominant phases along with a small amount of Ti3SiC2 phase and unreacted C left in the final products. As Fe content ranges from 10% to 30%, the products consist of TiC, Ti5Si3, Fe2Ti and unreacted C, but no trace of Ti3SiC2 phase is detected. Furthermore, the amounts of both Fe2Ti and C phases increase with Fe content increasing. Addition of Fe has a great effect on the reaction route and significantly restrains the formation of Ti3SiC2 during the combustion synthesis process, and therefore, the ShS is not an effective fabrication technique to synthesize the ternary Ti3SiC2 ceramic in either 3Ti-Si-2C or Fe-3Ti-Si-2C system. Besides, without Fe addition, Ti5Si3 presents as the coarse irregular appearance with an obviously sintered morphology. In contrast, the shape of Ti5Si3 exhibits more and more spherical (cobblestone-like) and the surface becomes increasingly smooth, because the amount of liquids formed during the ShS reaction increases with the increase of Fe content. On the other hand, with Fe content increasing from 0 to 30 wt.%, the particulate size of TiC decreases from more than 5 μm to 1 μm or less, mainly due to the fact that the combustion temperature decreases with the increase of Fe content in the preforms.

关键词：复合材料铁含量燃烧过程物理性能

Macroscopic and microscopic mechanical behaviors of climbing tendrils

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Acta Mechanica Sinica 2019年第3期35卷 702-710页

作者： q.Guo J.J.Dong Y.Liu X.h.Xu q.h.q.n J.S.wang Tianjin Key Laboratory of Modern Engineering Mechanics Department of MechanicsTianjin UniversityTianjin 300054China State Key Laboratory of Nonlinear Mechanics (LNM) Institute of MechanicsChinese Academy of ScienceBeijing 100080China Research School of Engineering Australian National UniversityCanberraACT 2601Australia

Tendril-bearing climbing plants must recur to the tendril helices with chiral perversion or dual chirality for climbing and to obtain sun exposure. Despite researchers' prolonged fascination with climbing tendrils since Darwin's time and even earlier, why the soft and slender tendrils can bear heavy loads such as the self-weight of a plant or additional load caused by rain remains elusive. In this paper, we take towel gourd tendrils as an example and investigate the macroscopic and microscopic mechanical behaviors of tendrils through experiments and simulations. Our study indicates that the tendril filament exhibits rubber-like hyperelastic behaviors and can particularly endure large elongation, which is mainly attributed to the superelasticity of the cellulose fibril helix contained in the cell wall. Combination of the tendril helical structure with dual chirality or chiral perversion at a macroscale and a cellulose filament helix at a subcellular level creates superior elasticity for biological species relying on support and climbing. This study provides deep insight into the structure-property relationship of climbing tendrils, and the relationship is useful for the bioinspired design of composite systems with superior elasticity.

关键词： Climbing tendril Mechanical behaviors Structure-property relationship Large elongation

Oxygen and Nitrogen Effects on MC Carbide in K465 Nickel-Base Superalloy

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稀有金属材料与工程 2009年第A3期38卷 13-16页

作者： wang L N Zheng q Sun X F Guan h R hu Z q Institute of Metals Research Chinese Academy of Sciences Shenyang 110015 China

Effects of oxygen and nitrogen on MC carbide in nickel-base superalloy K465 were investigated, because neither of the two gas elements was found to decide MC carbide morphology monotonically. The morphology of MC carbide under alloy solidified in conventional investment casting condition was observed to transform from script-type to block-type with the total oxygen and nitrogen content (gas content) in samples rising up from 1.2×10-6 mol/g to 2.6×10-6 mol/g. The area fraction and composition of the MC carbide also varied with increase of gas content. however, the morphology of MC carbide kept to be script-type even when gas content was up to 3.4×10-6 mol/g in samples solidified with a much higher cooling rate. These results indicate that effects of gas content on formation of MC carbide can be observed in specimens solidified with low cooling rate, but such changes in MC carbide cannot be found when the cooling rate is high.

关键词：氧碳化物氮含量物理性能碳化物