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Impact of H_(2)S on Hg^(0)capture performance over nitrogen-doped carbon microsphere sorbent:experimental and theoretical insights

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 89-100页

作者： Guopei zhang Xiaoyang zhang Xiangwen xing Xiangru Kong Lin Cui dong Yong National Engineering Laboratory for Reducing Emissions from Coal Combustion Shandong UniversityJinan250061China Bingtuan Energy Development Institute Shihezi UniversityShihezi832000China

A nitrogen-doped carbon microsphere sorbent with a hierarchical porous structure was synthesized via aggregation-hydrothermal *** Hg^(0)adsorption performance of the nitrogen-doped carbon microsphere sorbent was tested and compared with that of the coconut shell activated carbon prepared in the *** effect of H_(2)S on Hg^(0)adsorption was also *** nitrogen-doped carbon microsphere sorbent exhibited superior mercury removal performance compared with that of coconut shell activated *** the absence of H_(2)S at a low temperature(≤100℃),the Hg^(0)removal efficiency of the nitrogen-doped carbon microsphere sorbent exceeded 90%.This value is significantly higher than that of coconut shell activated carbon,which is approximately 45%.H_(2)S significantly enhanced the Hg^(0)removal performance of the nitrogen-doped carbon microsphere sorbent at higher temperatures(100–180℃).The hierarchical porous structure facilitated the diffusion and adsorption of H_(2)S and Hg^(0),while the nitrogen-containing active sites significantly improved the adsorption and dissociation capabilities of H_(2)S,contributing to the generation of more active sulfur species on the surface of the nitrogen-doped carbon microsphere *** formation of active sulfur species and HgS on the sorbent surface was further confirmed using X-ray photoelectron spectroscopy and Hg^(0)temperature-programmed desorption *** functional theory was employed to elucidate the adsorption and transformation of Hg^(0)on the sorbent surface.H_(2)S adsorbed and dissociated on the sorbent surface,generating active sulfur species that reacted with gaseous Hg^(0)to form HgS.

关键词： nitrogen-doped carbon microsphere H_(2)S Hg^(0)removal adsorption mechanism

基于静态法和动态热机械分析法的炭/炭复合材料性能的研究

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炭素技术 2024年第4期43卷 30-34页

作者：曹大可田远万德田张东兴杨昊天吴昊龙中国国检测试控股集团股份有限公司北京100024 中国建筑材料科学研究总院北京100024

采用静态三点弯曲法和动态热机械分析法的三点弯曲温度扫描模式(DMA)对2D-C/C复合材料进行了测试,探究其在室温和高温下的力学性能和阻尼性能。此外,对C/C复合材料进行了不同时长的低温氧化(350℃),配合扫描电镜分析了氧化时间对材料氧... 详细信息

采用静态三点弯曲法和动态热机械分析法的三点弯曲温度扫描模式(DMA)对2D-C/C复合材料进行了测试,探究其在室温和高温下的力学性能和阻尼性能。此外,对C/C复合材料进行了不同时长的低温氧化(350℃),配合扫描电镜分析了氧化时间对材料氧化程度和残余力学性能的影响。在室温下材料的三点弯曲强度和模量为671.6 MPa和44.3 GPa,当三点弯曲测试温度上升到300℃以上时,材料的弯曲强度和模量下降为41.5 MPa和4.7 GPa;使用DMA测试的结果显示了相同的趋势,DMA在室温下测试的弯曲模量为45.9 GPa,在300℃后材料的模量降低到非常低的水平,此外材料在210℃出现了明显的阻尼峰,tanδ约为0.14。实验还发现在72 h氧化后材料的失重率达到7.5%,弯曲强度和模量退化了约为72.1%和27.8%。最后通过扫描电镜对氧化后的试样形貌进行表征后发现复合材料的纤维和基体间隙随着氧化时间的增加越来越大,并且基体炭在72 h氧化后所剩无几,此外纤维在长时间氧化后表面粗糙不平并发现团聚的杂质元素结块。

关键词：炭/炭复合材料三点弯曲动态热机械分析法氧化行为微观形貌

Effects of subsoiling depth,period interval and combined tillage practice on soil properties and yield in the Huang-Huai-Hai Plain,China

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Journal of Integrative Agriculture 2020年第6期19卷 1596-1608页

作者： WANG Yun-xia CHEN Shu-ping zhang dong-xing YANG Li CUI Tao JING Hui-rong LI Yu-huan College of Engineering China Agricultural UniversityBeijing 100083P.R.China Dryland Farming Institute Hebei Academy of Agriculture and Forestry SciencesHengshui 053000P.R.China

Compact!on layers are widely distributed in the Huang-Huai-Hai Plain,China,which restrict root growth and reduce *** adoption of subsoiling has been recommended to disrupt compacted soil layers and create a reasonable soil structure for crop *** this paper,the effects of subsoiling depth(30,35 and 40 cm),period interval(2 or 3 years)and combined pre-sowing tillage practice(rotary cultivation or ploughing)on soil condition improvement was studied on a tidal soil in the Huang-Huai-Hai *** n tillage patter ns were desig ned by combini ng differe nt subsoili ng depths,period intervals and *** evaluation indicators for soil condition improvement were as follows:thickness of the plough layer and hard pan,soil bulk density,cone index,soil three-phase R values,alkali nitrogen content,crop yield,and economic ben *** results showed that subsoiling can sign ificantly improve the soil structure and physical *** all subsoiling treatments,the depth of 35 or 40 cm at a 2-year interval was the most *** thickness of the plough layer in creased from 13.67 cm before the test to 21.54-23.45 cm in *** thick ness of the hard pan decreased from 17.68 cm before the test to 12.09-12.76 cm in 2018,a decrease of about 40.07%.However,the subsoiling combined presowing tillage practice,that is,rotary cultivation or ploughing,was not significant for soil structure and physical *** all subsoiling treatments,the soil bulk density,cone index and soil three-phase R values of the 15-25 cm soil layer were significantly lower compared to single rotary *** was observed to increase the soil alkaline nitrogen and water conte *** tillage patter ns that had subsoiling at the depth of 35-40 cm at a 2-year in terval combi ned with rotary cultivation had the highest alkali nitrogen and water contents,which increased by 31.08-34.23%compared with that of the single rotary cultivati *** can sign ifica n

关键词： subsoiling period interval soil properties crop yield Huang-Huai-Hai Plain

Tuning mechanical and electrical performances of B_(4)C-TiB_(2)ceramics in a two-step spark plasma sintering process

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Journal of Advanced Ceramics 2024年第4期13卷 518-528页

作者： Jun Zhao xingshuo zhang Zongning Ma dong Wang xing Jin Songlin Ran Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243002China Anhui Engineering Research Center for High Efficiency Intelligent Photovoltaic Module Chaohu UniversityHefei 238024China

B_(4)C–TiB_(2)is an advanced electrically conductive ceramic with excellent mechanical and electrical discharge machinable *** is challenging and rewarding to achieve highly conductive and hard B_(4)C–TiB_(2)composites at a minimum content of conductive TiB2 that has inferior hardness but double specific gravity of the B_(4)C matrix.A novel strategy was used to construct conductive networks in B_(4)C‒15 vol%TiB2 composite ceramics with B_(4)C,TiC,and amorphous B as raw materials by a two-step spark plasma sintering *** influences of particle size matching between B_(4)C and TiC on the conducting of the strategy and the microstructure were discussed based on the selective matrix grain growth *** mechanical and electrical properties were also systematically *** B_(4)C–15 vol%TiB2 composite ceramic prepared from 10.29µm B_(4)C and 0.05µm TiC powders exhibited a perfect three-dimensional interconnected conductive network with a maximum electrical conductivity of 4.25×10^(4)S/m,together with excellent mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 691±58 MPa,30.30±0.61 GPa,and 5.75±0.32 MPa·m^(1/2),respectively,while the composite obtained from 3.12µm B_(4)C and 0.8µm TiC powders had the best mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 827±35 MPa,32.01±0.51 GPa,and 6.45±0.22 MPa·m^(1/2),together with a decent electrical conductivity of 0.65×10^(4)S/m.

关键词： B_(4)C-TiB_(2) mechanical properties electrical conductivity conductive network

Research on the Dynamic Compressibility of Polyurethane Microcellular Elastomer and its Application for Impact Resistance

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Chinese Journal of Polymer Science 2024年第8期42卷 1185-1197页

作者： Zhi-Ying Zhao Hao Jiang Xiao-dong Li Xu-dong zhang xing Su Mei-Shuai Zou School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

The packaging materials with cushioning performance are used to prevent the internal contents from being damaged by the impact and vibration of external *** polyurethane microcellular elastomers(PUMEs)can absorb energy through cell collapse and molecular chain *** this study,PUMEs with different densities were investigated by scanning electron microscopy,dynamic mechanical analysis and dynamic compression *** exhibited significant im pact resistance and the maximum peak stress attenuation ratio reached 73.33%.The protective equipment was made by PUME with the optimal density of 600 kg/m^(3),and then the acceleration sensing device installed with the same protective equipment fell from a height of 3,5 and 10 m to evaluate the energy-absorbing property and reusability of *** results showed that PUMEs equipment reduced the peak acceleration of the device by 93.84%,with a maximum deviation of 9%between actual test and simulation,and shortened the impact time of first landing by 57.39%.In addition,the equipment PUMEs equipment could effectively reduce the stress on the protected items.

关键词： Polyurethane microcellular elastomer Impact velocity Stress attenuation ratio Impact resistance

3D finite-difference modeling algorithm and anomaly features of ZTEM

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Applied Geophysics 2016年第3期13卷 553-560,582页

作者： Wang Tao Tan Han-dong. Li Zhi-Qiang Wang Kun-Peng Hu Zhi-Ming zhang xing-dong Key Laboratory of Geo-detection Ministry of Education and School of Geophysics and Information Technology China University of Geosciences Beijing 100083 China.

The Z-Axis tiPPer eiectromagnetic （ZTEM） technique is based on a frequency-domain airbome electromagnetic system that measures the natural magnetic field. A survey area was divided into several blocks by using the Maxwell＇s equations, and the magnetic components at the center of each edge of the grid cell are evaluated by applying the staggered-grid finite-difference method. The tipper and its divergence are derived to complete the 3D ZTEM forward modeling algorithm. A synthetic model is then used to compare the responses with those of 2D finite-element forward modeling to verify the accuracy of the algorithm. ZTEM offers high horizontal resolution to both simple and complex distributions of conductivity. This work is the theoretical foundation for the interpretation of ZTEM data and the study of 3D ZTEM inversion.

关键词： Z-Axis tipper electromagnetic finite-difference method tipper three-dimensional forward modeling airbome electromagnetic

Influence of voids on interlaminar shear strength of carbon/epoxy fabric laminates

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Transactions of Nonferrous Metals Society of China 2009年第S02期19卷 470-475页

作者： ZHU Hong-yan LI Di-hong zhang dong-xing WU Bao-chang CHEN Yu-yong School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Harbin Aircraft Industry Co. Ltd.Harbin 150060China

The effects of voids(void content,void shape and size)on the interlaminar shear strength of[(±45)_(4)/(0,90)/(±45)_(2)]_(S) and [(±45)/0_(4)/(0,90)/0_(2)]_(S) composite laminates were *** with void contents in the range of 0.2%-8.0%for [(±45)_(4)/(0,90)/(±45)_(2)]_(S) and 0.2%-6.1%for[(±45)/0_(4)/(0,90)/0_(2)]_(S) were fabricated from carbon/epoxy fabric through varying autoclave *** characteristics of the voids were studied by using optical image analysis to explain the interlaminar shear strength *** influences of voids on the interlaminar shear strength of the two stacking sequences were compared in terms of the void content and size and shape of the *** effect of voids on the initiation and propagation of interlaminar failure of both stacking sequence composites was found.

关键词： carbon fibre reinforced polymer(CFRP)composite void content void size void shape interlaminar shears strength

High-speed PGC demodulation model and method with subnanometer displacement resolution in a fiber-optic micro-probe laser interferometer

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Photonics Research 2024年第5期12卷 921-931页

作者： YISI dong WENWEN LI JiNRAN zhang WENRUI LUo HAIJIN FU XU xing PENGCHENG HU YONGKANG dong JIUBIN TAN Center of Ultra-precision Optoelectronic Instrument Harbin Institute of TechnologyHarbin 150080China Key Laboratory of Ultra-precision Intelligent Instrumentation(Harbin Institute of Technology) Ministry of Industry and Information TechnologyHarbin 150080China National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of TechnologyHarbin 150001China

As the key of embedded displacement measurement,a fiber-optic micro-probe laser interferometer(FMI)is of great interest in developing high-end equipment as well as precision ***,conventional phasegenerated carrier(PGC)approaches are for low-speed scenes and local error analysis,usually neglecting the global precision analysis and dynamic effect of system parameters under high-speed measurement,thus hindering their broad *** present a high-speed PGC demodulation model and method to achieve subnanometer displacement measurement precision in *** model includes a global equivalent resolution analysis and revelation of the demodulation error *** this model,the failure issues regarding the PGC demodulation method under high speed and large range are ***,an ultra-precision PGC demodulation algorithm based on the combination of static and dynamic delay adaptive regulation is proposed to enable high-speed and large-range displacement *** this paper,the proposed model and algorithm are validated through simulation and experimental *** results demonstrate a displacement resolution of 0.1 nm with a standard deviation of less than 0.5 nm when measuring at a high velocity of 1.5 m/s—nearly a tenfold increase of the latest study.

关键词： interferometer fiber displacement

Photo-induced tunable luminescence from an aggregated amphiphilic ethylene-pyrene derivative in aqueous media

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Chinese Chemical Letters 2024年第6期35卷 303-306页

作者： Junying zhang Ruochen Li Haihua Wang Wenbing Kang xing-dong Xu National Engineering Research Center for Colloidal Materials Key Laboratory of Special Functional Aggregated Materials of Ministry of EducationShandong Key Laboratory of Advanced Silicone Materials and TechnologySchool of Chemistry and Chemical EngineeringShandong UniversityJi’nan 250100China

An amphiphilic derivative with a large Stokes shift by introducing flexible hydrophilic long chains into a rigid ethylene-pyrene compound have been successfully *** alkylated compound exhibited a notable change in charge distribution,facilitating cation-π *** the process of amphiphilic self-assembly,the formation of highly ordered aggregates enabled effective photo-dimerization under 449 nm LED ***,this photo-responsive technology not only exhibited advanced multi-color emission effects,including white light emission but also exhibited environmentally friendly behavior in the aqueous phase.

关键词： Supramolecular chemistry Amphiphilic assembly Stimuli-responsive materials Tunable luminescence Pyrene derivative