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Synthesis of mordenite by solvent-free method and its application in the dimethyl ether carbonylation reaction
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作者 Yinghui Liu Shaoduo Liu +8 位作者 Xiaosheng Wang Hongjing Wang Ranjia Li Changchun Yu Chunming Xu Yuxiang Liu Zhengqiu Xie Yongqiang Wang Pan Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期216-223,共8页
Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sit... Mordenite with different Si/Al ratios were synthesized by solvent-free method and used for dimethyl ether(DME)carbonylation reaction.The influence of Si/Al ratio in the feedstock on the structure,porosity and acid sites were systematically investigated.The characterization results showed that with the increase of Si/Al ratio in the feedstock,part of silicon species fail to enter the skeleton and the specific surface area and pore volume of the samples decreased.The amount of weak acid and medium strong acid decreased alongside with the increasing Si/Al ratio,and the amount of strong acid slightly increased.The Al atoms preferentially enter the strong acid sites in the 8 member ring(MR)channel during the crystallization process.The high Si/Al ratio sample had more acid sites located in the 8 MR channel,leading to more active sites for carbonylation reaction and higher catalytic performance.Appropriately increasing the Si/Al ratio was beneficial for the improvement of carbonylation reaction activity over the mordenite(MOR)catalyst. 展开更多
关键词 CARBONYLATION Dimethyl ether SOLVENT-FREE ZEOLITE Synthesis CATALYSIS
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Interfacial engineering through lead binding using crown ethers in perovskite solar cells
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作者 Sun-Ju Kim YeonJu Kim +8 位作者 Ramesh Kumar Chitumalla Gayoung Ham Thanh-Danh Nguyen Joonkyung Jang Hyojung Cha Jovana Milić Jun-Ho Yum Kevin Sivula Ji-Youn Seo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期263-270,共8页
In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an ... In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial passivation.Crown ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material interface.Crown ethers exhibit a dual role:efficiently sequestering and immobilizing Pb^(2+)ions through host-guest complexation and simultaneously establishing a robust interfacial passivation layer.Selected crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial energetics.Photovoltaic devices incorporating these materials achieved exceptional power conversion efficiency(PCE),notably 21.7%for B18C6,underscoring their efficacy in lead binding and interfacial passivation.Analytical techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photoluminescence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb^(2+)ion capture and suppression of non-radiative recombination.Notably,these PSCs maintained efficiency even after enduring 300 h of exposure to 85%relative humidity.This research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications. 展开更多
关键词 Perovskite solar cells Interfacial passivation Crown ether materials Stability
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The effect of salt anion in ether‐based electrolyte for electrochemical performance of sodium‐ion batteries:A case study of hard carbon
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作者 Jiabao Li Jingjing Hao +6 位作者 Quan Yuan Ruoxing Wang Frederick Marlton Tianyi Wang Chengyin Wang Xin Guo Guoxiu Wang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期285-297,共13页
Compared with the extensively used ester‐based electrolyte,the hard carbon(HC)electrode is more compatible with the ether‐based counterpart in sodium‐ion batteries,which can lead to improved cycling stability and r... Compared with the extensively used ester‐based electrolyte,the hard carbon(HC)electrode is more compatible with the ether‐based counterpart in sodium‐ion batteries,which can lead to improved cycling stability and robust rate capability.However,the impact of salt anion on the electrochemical performance of HC electrodes has yet to be fully understood.In this study,the anionic chemistry in regulating the stability of electrolytes and the performance of sodium‐ion batteries have been systematically investigated.This work shows discrepancies in the reductive stability of the anionic group,redox kinetics,and component/structure of solid electrolyte interface(SEI)with different salts(NaBF_(4),NaPF_(6),and NaSO_(3)CF_(3))in the typical ether solvent(diglyme).Particularly,the density functional theory calculation manifests the preferred decomposition of PF_(6)−due to the reduced reductive stability of anions in the solvation structure,thus leading to the formation of NaF‐rich SEI.Further investigation on redox kinetics reveals that the NaPF_(6)/diglyme can induce the fast ionic diffusion dynamic and low charge transfer barrier for HC electrode,thus resulting in superior sodium storage performance in terms of rate capability and cycling life,which outperforms those of NaBF_(4)/diglyme and NaSO_(3)CF_(3)/diglyme.Importantly,this work offers valuable insights for optimizing the electrochemical behaviors of electrode materials by regulating the anionic group in the electrolyte. 展开更多
关键词 ether‐based electrolyte reaction kinetics salt anion SEI components sodium storage
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TLC Identification and Extraction Process of Rubiasin-1-methyl Ether from Yao Medicine Chuanlianzhu
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作者 Jingrong LU Jiangcun WEI +3 位作者 Xiumei MA Bing QING Meiyan QIU Wen ZHONG 《Medicinal Plant》 2024年第3期35-38,共4页
[Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopte... [Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopted for TLC.Petroleum ether(60-90℃)-chloroform-methanol-water(7:15:3:1)was used as the developing solvent and inspected under ultraviolet lamp(365 nm).The content was determined by Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm),mobile phase:acetonitrile-0.2%phosphoric acid gradient elution,detection wavelength 277 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The spots of 10 Chuanlianzhu samples from different origins showed the same color at the same position as the control,and the spots were clear and specific.The injection volume of rubiadin-1-methyl ether showed a good linear relationship in the range of 2.90-145μg(R=0.9996).The average recovery rate of rubiadin-1-methyl ether in the low,medium and high dose groups of Yao Medicine Chuanlianzhu was 98.72%,and RSD=1.78%.[Conclusions]This method can effectively identify Yao Medicine Chuanlianzhu medicinal materials and accurately determine the content of rubiadin-1-methyl ether in the medicinal materials.It provides a scientific basis for the development and utilization of Yao Medicine Chuanlianzhu medicinal resources. 展开更多
关键词 Chuanlianzhu THIN-LAYER chromatography (TLC) Extraction process Rubiadin-1-methyl ether Content determination
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基于Arduino-EtherNet智能化远程测距系统设计
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作者 曾金 《智慧工厂》 2016年第5期76-77,88,共3页
本文介绍基于Arduino-Ether Net开源单片机智能化远程测距系统设计全过程,充分利用开源单片机Arduino-Ether Net开发简洁、功能强大、可独立运行等特点,采取温度补偿方法弥补超声波受温度影响,实时数据通过1602LCD显示,用于智能化实时... 本文介绍基于Arduino-Ether Net开源单片机智能化远程测距系统设计全过程,充分利用开源单片机Arduino-Ether Net开发简洁、功能强大、可独立运行等特点,采取温度补偿方法弥补超声波受温度影响,实时数据通过1602LCD显示,用于智能化实时检测距离,同时经过单片机处理后的实时数据通过网络传送到数据库中存储,并通过中间键建立通道实现实时数据显示在web界面,管理人员可以在远程实时监测到所需测试距离的数据,实现真正的智能化测试与安全监测。 展开更多
关键词 Arduino单片机 智能化 超声波 WEB
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Intrinsic Kinetics of Dimethyl Ether Synthesis from Syngas 被引量:3
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作者 ZhaoguangNie HongweiLiu +2 位作者 DianhuaLiu WeiyongYing DingyeFang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2005年第1期22-28,共7页
The intrinsic kinetics of dimethyl ether (DME) synthesis from syngas over amethanol synthesis catalyst mixed with methanol dehydration catalyst has been investigated in atubular integral reactor at 3-7 MPa and 220-260... The intrinsic kinetics of dimethyl ether (DME) synthesis from syngas over amethanol synthesis catalyst mixed with methanol dehydration catalyst has been investigated in atubular integral reactor at 3-7 MPa and 220-260℃. The three reactions including methanol synthesisfrom CO and H_2, CO_2 and H_2, and methanol dehydration were chosen as the independent reactions.The L-H kinetic model was presented for dimethyl ether synthesis and the parameters of the modelwere obtained by using simplex method combined with genetic algorithm. The model is reliableaccording to statistical analysis and residual error analysis. The synergy effect of the reactionsover the bifunctional catalyst was compared with the effect for methanol synthesis catalyst underthe same conditions based on the model. The effects of syngas containing Na on the reactions werealso simulated. 展开更多
关键词 dimethyl ether SYNTHESIS KInetICS SYNGAS
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Theoretical Studies on the Kinetics and Mechanisms of Reactions for Methyl Vinyl Ether and Ozone 被引量:1
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作者 Bo Long Ming-qiang Huang +1 位作者 Zhen-ya Wang Wei-jun Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第4期324-332,共9页
The interconversion between the two distinct isomers of methyl vinyl ether (MVE), the formation of the primary ozonides from O3-initated reactions of MVE, the transformation between the primary ozonides, and the sub... The interconversion between the two distinct isomers of methyl vinyl ether (MVE), the formation of the primary ozonides from O3-initated reactions of MVE, the transformation between the primary ozonides, and the subsequent fragmentation were studied using quantum chemical methods at the BHandHLYP/6311++G(d,p) level of theory for optimized geometries and frequency calculations and at the QCISD/631G(d,p) level for the single point energy calculations. The rate coefficients were calculated for the temperature range 280-440 K by using the canonical transition state theory (TST). For ozone addition to MVE, there are two different possibilities discussed on the basis of two different possible orientations for ozone attack. The results of the theoretical study indicate that although the synperiplanar-MVE is 7.11 kJ/mol more stable than the antiperiplanar-MVE, the antiperiplanar-MVE plays a more important role in formation of the primary ozonides because the primary ozonides formed from the ozone addition antiperiplanar-MVE are more stable and the energy barriers corresponding to transition states are lower. The intereonversion between the primary ozonides formed from the ozone addition to antiperiplanar-MVE is the most accessible compared with the transformations between other primary ozonides. The cleavage of the primary ozonides mainly leads to the formation of the CH2OO, which is in agreement with the experimental estimates. The calculated overall rate constant for the ozone-initiated reactions is 4.8× 10^-17 cm^3/(molecule.s) at 298.15 K, which agrees with the experimental value for ethyl vinyl ether. 展开更多
关键词 Methyl vinyl ether OZONE Reaction pathway Primary ozonide INTERCONVERSION Rate constant Transition state theory
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Cosmic Ether, Possessing Electric-Tension and Magnetic-Resistance, Is the Unified Field for Physics 被引量:1
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作者 Chandrasekhar Roychoudhuri 《Journal of Modern Physics》 2021年第5期671-699,共29页
The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of ... The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of this energetic tension field as the electric-tension, <img src="Edit_1233fa02-9a1c-416a-8153-196733a12887.png" alt="" />, and the magnetic-resistance, <em>μ</em><sub>0</sub>, while re-deriving the Maxwell’s wave equation in analogy with the mechanically stretched string, where the <img src="Edit_07813a1b-d94f-4e68-a3ed-b3023cd3fb5f.png" alt="" />. Then, replacing <img src="Edit_7d06fa1e-760d-4b80-a503-db81378a3512.png" alt="" /> by <img src="Edit_58f15ef0-2e86-42ae-a899-d0b4741f12d0.png" alt="" /> and <em>m</em><sub>0</sub> by <img src="Edit_f8cb7020-1a27-404a-b146-5c1357e1c5b5.png" alt="" />, one can find that almost all working physics theories are being energized by<img src="Edit_f860fcdd-1dc1-40bf-aaf1-e07b0e4a7524.png" alt="" />and <em>μ</em><sub>0</sub>. To complete the unification, we can now postulate that the particles are also freely propagating EM waves, but they are spatially localized as in-phase, close-looped (IP-CL) vortex-like propagation modes of ether. Because of their IP-CL mode structure, they have space-finite spatial structures and remain spatially stationary in the absence of any spatially influencing potential gradients (forces) in their vicinity. Particles’ <em>harmonic phase</em> driven interactions between quantum particles give birth to the <em>appearance</em> of wave-particle duality. There is no need for the confusing and unnecessary de Broglie’s Pilot Wave. The inertia to spatial motion of IP-CL modes automatically accommodates Newton’s laws of motion. The cosmic universality of Maxwellian wave velocity, and particles as IP-CL modes, jointly accommodate the two key postulates of special relativity without the need for unphysical four-dimensionality. The observable universe is represented only by its diverse oscillatory excited states. The stable and stationary Cosmic Ether keeps holding 100% of its energy all the time. We have proposed a one-way light pulse propagation experiment to directly validate the existence of ether, rather than approaching Michelson’s way of measuring the ether drag. We have identified a good number of examples of working theoretical expressions in terms of <img src="Edit_fd739625-efbd-4edd-9e1e-ba4ab5b7c07f.png" alt="" />and<em> μ</em><sub>0</sub> and presented our critical views in physics thinking, belonging to Classical, Relativity, Quantum and Cosmology Physics. 展开更多
关键词 Cosmic ether ether as the Unifying Field ether Energetic Tension Field (1/ε0)-Electric Tension of ether μ0-Magnetic Resistance of ether Particles as Localized EM Oscillating Modes of ether
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NETWORK CROWN ETHER POLYMERS WITH CENTRIC FUNCTIONAL GROUPS.Ⅱ.SYNTHESIS OF NETWORK CROWN ETHER POLYMER WITH PENDANT SULFIDE SIDE CHAIN AND ITS PLATINUM COMPLEX 被引量:1
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作者 CHEN Yuanyin MENG Lingzhi YIN Yihua 《Chinese Journal of Reactive Polymers》 1995年第1期53-60,共8页
Network crewn ether polymer with pendant sulfide side ohain in the networkstructure units has been synthesized via ring- opening copolymerization of β-ethylthioethyl glycidyl ether and diethylene glycol bisglycidyl e... Network crewn ether polymer with pendant sulfide side ohain in the networkstructure units has been synthesized via ring- opening copolymerization of β-ethylthioethyl glycidyl ether and diethylene glycol bisglycidyl ether. A kind of active catalyst suitable for this reaction was suggested. The title polymer was found tobe a good ligand for platinous chloride, and the platinous complex could catalyze thehydrosilylation of olefins with triethoxysilane efficiently. 展开更多
关键词 Crown ether Polymeric crown ether Sulfide platinum complex Hydrosilylation catalyst PLATINUM
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Kinetic Study of Methanol Dehydration to Dimethyl Ether in Catalytic Packed Bed Reactor over Resin 被引量:1
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作者 Ghassan J. Hadi Arkan J. Hadi 《Journal of Materials Science and Chemical Engineering》 2022年第6期45-58,共14页
Dimethyl ether (DME) is considered as a significant fuel alternative with a critical manufacturing process. Only a few authors have presented the kinetic analysis of attractive and alternative catalysts to Al<sub&g... Dimethyl ether (DME) is considered as a significant fuel alternative with a critical manufacturing process. Only a few authors have presented the kinetic analysis of attractive and alternative catalysts to Al<sub>2</sub>O<sub>3</sub> and/or zeolite in DME production, despite the fact that there is a large library of kinetic studies for these commercial catalysts. The purpose of this research was to contribute to this direction by conducting a catalytic test to determine kinetic parameters for methanol dehydration over sulfonic acid catalysts (resin). However, due to the relevance of the mathematical description of this process in the industry was also studied, a study of kinetics parameters and mathematical modeling of methanol dehydration in an atmospheric gas phase in a fixed bed reactor with a temperature range (90&degC - 120&degC) was examined. The Langmuir-Hinshelwood (L-H) model provides the best fit to experimental data, with an excellent R<sup>2</sup> = 0.9997, and the experimental results were compared to those predicted by these models with very small deviations. The kinetic parameters were found to be in good agreement with the Arrhenius equation, with acceptable straight-line graphs. The activation energy E was computed and found to be 27.66 kJ/mole, with an average variation of 0.32 percent between the predicted and calculated results. Simple mathematical continuum models (plug flow reactor PFR) showed an acceptable agreement with the experimental data. 展开更多
关键词 CATALYST Dimethyl ether Fixed Bed Reactor DEHYDRATION MODELLING
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Economy, environmental assessment and energy conservation for separation of isopropanol/diisopropyl ether/water multi-azeotropes via extractive distillation coupled pervaporation process 被引量:2
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作者 Qinggang Xu Yasen Dai +6 位作者 Qing Zhao Zhengrun Chen Peizhe Cui Zhaoyou Zhu Yinglong Wang Jun Gao Yixin Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期353-363,共11页
This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heteroge... This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heterogeneous azeotropes in industrial wastewater from the synthesis of isopropanol in this study.Based on strict design specifications, simulation and sequential iteration methods are used for process design and optimization. Compared to the ethylene glycol(EG)-EG+H_(2)O process and the 1,3-propanediol(PDO)-IPA+H_(2)O process, the total annual cost(TAC) of the EG-IPA+H_(2)O process decreased by 20.76% and 7.86%(PDO). Compared to the EG-EG+H_(2)O process, the TAC of the PDO-IPA+H_(2)O process reduced 14%, but the global warming potential(GWP) and human toxicity of the PDO-IPA+H_(2)O process increased 11.3% and 4.07% respectively. Compared to the PDO-IPA+H_(2)O process, the EG-IPA+H_(2)O process saves 7.86%(TAC), 9.78%(GWP) and 9.85%(human toxicity). The ED+PV process with EG is superior to PDO in factors of TAC, energy consumption, human toxicity and environment. The EG-IPA+H_(2)O process changed the separation order of the products of the multi-azeotropic system, reduced the cost and energy conservation of the system, and enhanced the environmental protection evaluation of the process, is the best process through life cycle assessment for analyzing the economy, energy conservation, environmental assessment and human toxicity, designing cleaner products, controlling waste discharge, and promoting the chemical purification industry. This work provides a new process design and optimized separation ideas, will have a good guiding significance for the research and application separation of multi-azeotropic mixture with mixed solvents in organic wastewater from the cleaner chemical production, has been up to standard wastewater discharge process, and realized the development goal of carbon peak and carbon neutrality in the sustainable development of chemical clean industry. 展开更多
关键词 Life cycle assessment Extractive distillation coupled pervaporation Isopropanol/diisopropyl ether/water azeotropes Thermodynamic efficiency Human toxicity
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NETWORK CROWN ETHER POLYMERS WITH CENTRIC FUNCTIONAL GROUP (Ⅳ) SYNTHESIS OF NETWORK CROWN ETHER POLYMER WITH PENDANT DIETHYLAMINO THIAALKYL GROUP AND ITS PLATINUM COMPLEX
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作者 陈远荫 孟令芝 +1 位作者 殷以华 耿成爱 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第4期316-322,共7页
The title polymer was prepared from 5-diethylamino-3-thia-pentyl glycidyl ether anddiethylene glycol bisglycidyl ether via ring-opening copolymerization. It was found that thisreaction could be catalyzed by sodium, bu... The title polymer was prepared from 5-diethylamino-3-thia-pentyl glycidyl ether anddiethylene glycol bisglycidyl ether via ring-opening copolymerization. It was found that thisreaction could be catalyzed by sodium, but not Lewis acid. The obtained polymer can coordinatewith platinum compound, and the platinum complex is a new kind of catalyst for thehydrosilylation of olefins with triethoxysilane. 展开更多
关键词 Crown ether Crown ether polymer Platinum complex Hydrosilylation catalyst
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Formation kinetics of polyoxymethylene dimethyl ethers from methylal and trioxane with little water
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作者 Xiaofei Qin Sen Lei +6 位作者 Xubin Zhang Chen Cao Feng Xin Honglin Chen Xiaoming Zhang Yachen Yin Guilian Wu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第5期139-146,共8页
Polyoxymethylene dimethyl ethers(CH_(3)-O-(CH_(2)O)_(n)-CH_(3),PODE_(n),n>1)can be added to diesel to reduce air pollution caused by incomplete combustion.Driven by this need,a cost-effective and efficient syntheti... Polyoxymethylene dimethyl ethers(CH_(3)-O-(CH_(2)O)_(n)-CH_(3),PODE_(n),n>1)can be added to diesel to reduce air pollution caused by incomplete combustion.Driven by this need,a cost-effective and efficient synthetic route is presented and investigated by this work for the production of PODE_(n),which are formed from methylal and trioxane with low water content(<10%(mass))over HZSM-5 catalyst in a batch slurry autoclave at the temperature from 353.15 K to 393.15 K.The reaction rate laws including the PODE_(n) and byproducts of polyoxymethylene hemiformals(HF_(n)),polyoxymethylene glycols(MG),methanol(MeOH)and methyl formate(MF)are developed.The rate constants of propagation step(k_(6))and depolymerization step(k_(-6))are assumed independent on polymerization degree of PODE_(n).The rate of reaction is proportional to the content of the catalyst(Wcat)for the catalytic reaction within the scope of the study.All kinetic parameters were estimated by combining genetic algorithm and least square regression to fit experimental data well.This work is valuable for process optimization and reactor design. 展开更多
关键词 Fuel additive POLYOXYMETHYLENE DIMETHYL etherS KInetICS HZSM-5
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Ether/Netware网在聚酯生产数据采集系统中的应用
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作者 白秀琪 《聚酯工业》 CAS 1990年第1期36-40,共5页
介绍该网络系统的技术特点和功能。开发聚酯生产的氧化—缩聚—生产调度—仪表车间的数据采集监测系统,有硬件配置、信号采集、处理及入网情况与特点,实现生产过程计算机管理自动化。
关键词 数据采集系统 ether/netware 聚酯生产 监测系统 硬件配置 生产调度 生产过程 管理自动化 网络系统 手工记录
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Harnessing dimethyl ether and methyl formate fuels for direct electrochemical energy conversion
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作者 Medhanie Gebremedhin Gebru Radhey Shyam Yadav +3 位作者 Hanan Teller Haya Kornweitz Palaniappan Subramanian Alex Schechter 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期454-464,I0012,共12页
In this work,the oxidation of a mixture of dimethyl ether(DME) and methyl formate(MF) was studied in both an aqueous electrochemical cell and a vapor-fed polymer electrolyte membrane fuel cell(PEMFC)utilizing a multi-... In this work,the oxidation of a mixture of dimethyl ether(DME) and methyl formate(MF) was studied in both an aqueous electrochemical cell and a vapor-fed polymer electrolyte membrane fuel cell(PEMFC)utilizing a multi-metallic alloy catalyst,Pt_(3)Pd_(3)Sn_(2)/C,discovered earlier by us.The current obtained during the bulk oxidation of a DME-saturated 1 M MF was higher than the summation of the currents provided by the two fuels separately,suggesting the cooperative effect of mixing these fuels.A significant increase in the anodic charge was realized during oxidative stripping of a pre-adsorbed DME+MF mixture as compared to DME or MF individually.This is ascribed to greater utilization of specific catalytic sites on account of the relatively lower adsorption energy of the dual-molecules than of the sum of the individual molecules as confirmed by the density fu nctional theory(DFT) calculations.Fuel cell polarization was also conducted using a Pt_(3)Pd_(3)Sn_(2)/C(anode) and Pt/C(cathode) catalysts-coated membrane(CCM).The enhanced surface coverage and active site utilization resulted in providing a higher peak power density by the DME+MF mixture-fed fuel cell(123 mW cm^(-2)at 0.45 V) than with DME(84mW cm^(-2)at 0.35 V) or MF(28 mW cm^(-2)at 0.2 V) at the same total anode hydrocarbon flow rate,temperature,and ambient pressure. 展开更多
关键词 Dimethyl ether Methyl formate Fuel cell ELECTROCATALYSIS Multi-metallic alloy
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Durable semi-crystalline interphase engineering to stabilize high voltage Ni-rich cathode in dilute ether electrolyte
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作者 Zhuangzhuang Cui Shunqiang Chen +7 位作者 Qingshun Nian Yecheng Li Yawei Chen Bing-Qing Xiong Zihong Wang Zixu He Shuhong Jiao Xiaodi Ren 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期110-117,共8页
Ethers are promising electrolyte solvents for secondary Li metal batteries because of their excellent reduction stability.However,their oxidation stability has been mostly relying on the high concentration approach,an... Ethers are promising electrolyte solvents for secondary Li metal batteries because of their excellent reduction stability.However,their oxidation stability has been mostly relying on the high concentration approach,and limited progress has been made on building effective interphase to protect the cathode from the corrosion of the electrolyte.In this work,we construct a semi-crystalline interfacial layer on the surface of Li(Ni_(0.8)Co_(0.1)Mn_(0.1))O_(2)cathode that can achieve improved electrochemical stability in the highly corrosive chemical environment formed by the decomposition of ether molecules.Different from traditional brittle crystalline interphases,the optimized semi-crystalline layer with low modulus and high ionic conductivity can effectively relieve electrode strain and maintain the integrity of the interface layer.Due to this design,the continuous oxidation decomposition of ether-based electrolytes could be significantly suppressed and the battery shows outstanding cycling stability(84%capacity retention after 300 cycles).This article provides a solution to address the oxidation instability issue of ether-based electrolytes. 展开更多
关键词 Cathode/electrolyte interphase Semi-crystalline ether electrolyte High-voltage cathode Li-metal batteries
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Butyl ether as Co-diluent in medium-concentrated electrolyte for Li-S battery
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作者 Xirui Kong Yayun Zheng +2 位作者 Lang He Du Wang Yan Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期343-347,I0010,共6页
1. Introduction The Lithium-sulfur battery(LSB) shows promise as a highdensity energy source, with a theoretical energy density of approximately 2600 W h kg^(-1)[1]. However, practical application of the LSB has been ... 1. Introduction The Lithium-sulfur battery(LSB) shows promise as a highdensity energy source, with a theoretical energy density of approximately 2600 W h kg^(-1)[1]. However, practical application of the LSB has been hindered by the “shuttle effect” and Li anode corrosion [2,3]. Highly concentrated electrolytes(HCEs) have been proposed as a solution, as they can inhibit the dissolution of lithium polysulfide and promote homogeneous lithium deposition [4]. 展开更多
关键词 Lithium-sulfur battery Diluted electrolyte Butyl ether Co-diluent
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Li^(+)-ion bound crown ether functionalization enables dual promotion of dynamics and thermodynamics for ambient ammonia synthesis
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作者 Qiyang Cheng Sisi Liu +8 位作者 Mengfan Wang Lifang Zhang Yanzheng He Jiajie Ni Jingru Zhang Chengwei Deng Yi Sun Tao Qian Chenglin Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期191-197,I0007,共8页
Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous ... Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous efforts devoted to electrocatalysts themselves,they still fail to tackle the above two challenges simultaneously.Herein,we employ a heterogeneous catalyst adlayer-composed of crown ethers associated with Li^(+)ions-to achieve the dual promotion of dynamics and thermodynamics for ambient ammonia synthesis.Dynamically,the bound Li^(+)ions interact with the strong quadrupole moment of nitrogen,and trigger considerable reactant flux toward the catalyst.Thermodynamically,Li^(+)associated with the oxygen of crown ether achieves a higher density of states at the Fermi level for the catalyst,enabling effortless electron transfer from the catalysts to nitrogen and thus greatly reducing the activation barrier.As expected,the proof-of-concept system achieves an ammonia yield rate of 168.5μg h^(-1)mg^(-1)and a Faradaic efficiency of 75.3%at-0.3 V vs.RHE.This system-level approach opens up pathways for tackling the two key challenges that have limited the field of ammonia synthesis. 展开更多
关键词 Li^(+)-ion bound crown ether DYNAMICS Thermodynamics Nitrogen reduction Ammonia synthesis
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Density Functional Theory Study of Marine Polybrominated Diphenyl Ethers in Anaerobic Degradation
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作者 XU Xiang MAN Miaomiao +3 位作者 SUN Qinxing LIU Qingzhi WU Kechen YANG Dengfeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1353-1360,共8页
Polybrominated diphenyl ethers(PBDEs)are a kind of serious pollutants in the ocean.Biodegradation is considered as an economical and safe way for PBDEs removal and reductive debromination dominates the initial pathway... Polybrominated diphenyl ethers(PBDEs)are a kind of serious pollutants in the ocean.Biodegradation is considered as an economical and safe way for PBDEs removal and reductive debromination dominates the initial pathway of anaerobic degradation.On the basis of experimental study,Octa-BDE 197,Hepta-BDE 183,Hexa-BDE 153,Penta-BDE 99 and Tetra-BDE 47 were selected as the initial degradation objects,and their debromination degradation were studied using density functional theory.The structures were optimized by Gaussian 09 program.Furthermore,the molecular orbitals and charge distribution were analyzed.All C-Br bond dissociation energies at different positions including ortho,meta and para bromine atoms were calculated and the sequence of debromination was obtained.There is a close relationship between molecular structure,charge,molecular orbital and C-Br bond.All PBDEs exhibited similar debromination pathways with preferential removal of meta and para bromines. 展开更多
关键词 polybrominated diphenyl ethers reductive debromination anaerobic degradation density functional theory bond dissociation energies
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Functional zirconium phosphate nanosheets enabled transfer hydrogenolysis of aromatic ether bonds over a low usage of Ru nanocatalysts
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作者 Jinliang Song Yayun Pang +2 位作者 Chenglei Xiao Huizhen Liu Buxing Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期373-380,I0009,共9页
Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high activity.Herei... Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high activity.Herein,we designed porous zirconium phosphate nanosheet-supported Ru nanocatalysts(Ru/ZrPsheet)as the heterogeneous catalyst by a process combining ball milling and molten-salt(KNO_(3)).Very interestingly,the fabricated Ru/ZrPsheetshowed good catalytic performance on the transfer hydrogenolysis of various types of aromatic ether bonds contained in lignin,i.e.,4-O-5,a-O-4,β-O-4,and aryl-O-CH3,over a low Ru usage(<0.5 mol%)without using any acidic/basic additive.Detailed investigations indicated that the properties of Ru and the support were indispensable.The excellent activity of Ru/ZZrPsheetoriginated from the strong acidity and basicity of ZrPsheetand the higher electron density of metallic Ru0as well as the nanosheet structure of ZrPsheet. 展开更多
关键词 Valorization of lignin Aromatic ether bonds Transfer hydrogenolysis synergistic cooperation Zirconium phosphate nanosheets
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