JOURNAL OF CHEMICAL THERMODYNAMICS
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2017
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IF 2.726
Ying Zhang,Xinxin He,Yutian Chen,Maogang He
The mutual diffusion coefficients of n -butanol + n -heptane and n -pentanol + n -heptane were measured over the mass fraction of n -butanol or n -pentanol from 0.05 to 0.95 at intervals of 0.10 and the temperatures 288.15 K, 298.15 K, 308.15 K and 318.15 K at 0.101 MPa. The measurements were carried out using a digital holographic interferometry system. The expanded relative uncertainty of the mutual diffusion coefficients was estimated to be less than 2.4%. The influences of temperature and composition on the mutual diffusion coefficients were investigated. Moreover, equations for the mutual diffusion coefficients of the two binary mixtures were fitted to the data as functions of mass fraction and temperature. The correlations represent the data with the absolute average of relative deviations (AARDs) of 1.1% for n -butanol + n -heptane and 0.77% for n -pentanol + n -heptane, respectively.
研究领域:
物理化学
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热力学
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传递现象
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溶液化学
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流体混合物
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
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2015
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IF 4.504
Yan Zhang,Ming-Ming Gao,Xin-Hua Wang,Shu-Guang Wang,Rui-Ting Liu
An electro-Fenton process was developed for wastewater treatment in which hydrogen peroxide was generated in situ with a rotating graphite disk electrode as cathode. The maximum H 2 O 2 generation rate for the RDE reached 0.90 mg/L/h/cm 2 under the rotation speed of 400 rpm at pH 3, and −0.8 V vs SCE. The performance of this electro-Fenton reactor was assessed by tetracycline degradation in an aqueous solution. Experimental results showed the rotation of disk cathode resulted in the efficient production of H 2 O 2 without oxygen aeration, and excellent ability for degrading organic pollutants compared to the electro-Fenton system with fixed cathode. Tetracycline of 50 mg/L was degraded completely within 2 h with the addition of ferrous ion (1.0 mM). The chronoamperometry analysis was employed to investigate the oxygen diffusion on the rotating cathode. The results demonstrated that the diffusion coefficients of dissolved oxygen is 19.45 × 10 −5 cm 2 /s, which is greater than that reported in the literature. Further calculation indicated that oxygen is able to diffuse through the film on the rotating cathode within the contact time in each circle. This study proves that enhancement of oxygen diffusion on RDE is benefit for H 2 O 2 generation, thus provides a promising method for organic pollutants degradation by the combination of RDE with electro-Fenton reactor and offers a new insight on the oxygen transform process in this new system.
研究领域:
环境科学
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电化学
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水处理技术
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污染物降解
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反应工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2022
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IF 9.794
Zhengjian Li,Sian Chen,Liting Cui,Haining Wang,Shanfu Lu,Yan Xiang
The acidic-alkaline interface of a bipolar membrane fuel cell (BPMFC) is the place to generate water, which significantly affect the output performance of BPMFC by regulating the water distribution due to the ion conductivity and oxygen reduction reaction (ORR) kinetics in cathode. To investigate the influence of water diffusivity ( D w ) on the water distribution, four alkaline polymer electrolytes with different D w is selected as anion exchange membrane or alkaline electrolyte ionomer to assemble BPMFCs. A combined experimental and simulated study reveals the positive correlation relationship of D w to the water distribution and performance of BPMFC. By increasing the D w of the alkaline polymer electrolytes, the interfacial-generated water amount can be increased and promptly transport to the cathode, thereby satisfying the ion conductivity and increasing the ORR kinetics, and breakthrough the peak power density of the BPMFC with 1.06 W cm −2 without humidification .
研究领域:
电化学
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能源材料
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燃料电池
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高分子科学
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界面科学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2015
·
IF 4.504
Peng Li,Lianyi Shao,Pengfei Wang,Xi Zheng,Haoxiang Yu,Shangshu Qian,Miao Shui,Nengbing Long,Jie Shu
In this work, Li 2 NaV 2 (PO 4 ) 3 is successfully synthesized by using a simple solid-state reaction method. Structural analysis shows that this sample is a hybrid product consisted of rhombohedral Li 3 V 2 (PO 4 ) 3 phase and rhombohedral Na 3 V 2 (PO 4 ) 3 phase As a cathode material for lithium ion batteries, Li 2 NaV 2 (PO 4 ) 3 exhibits an initial reversible capacity of 108.9 mAh g −1 at 35 mA g −1 in the potential range between 3.0 and 4.3 V, with an average working potential at 3.75 V. The lithium-ion diffusion coefficient in Li 2 NaV 2 (PO 4 ) 3 is measured to be 1.86–3.27 × 10 −15 cm 2 s −1 . In addition, the electrochemical reaction between Li 2 NaV 2 (PO 4 ) 3 and Li is also investigated by various in-situ and ex-situ techniques. Viewed from the in-situ and ex-situ results, it is concluded that the electrochemical reactions of Li 2 NaV 2 (PO 4 ) 3 with Li are associated with the formation of rhombohedral LiV 2 (PO 4 ) 3 phase and rhombohedral NaV 2 (PO 4 ) 3 phase during the lithium ion extraction process and its reverse lithium insertion process is reversible for structural evolution. The highly stable structure ensures the electrochemical reversibility of Li 2 NaV 2 (PO 4 ) 3 cathode material in lithium ion batteries.
研究领域:
材料科学
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电化学
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能源存储
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无机化学
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固体化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2017
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IF 3.012
Haojie Zhu,Ke Yang,Hua Lan,Shangshu Qian,Haoxiang Yu,Lei Yan,Nengbing Long,Miao Shui,Jie Shu
In this work, Na 2 Ti 3 O 7 is fabricated as lithium storage material via one-step solid state reaction. Worked as anode material , Na 2 Ti 3 O 7 delivers a stable electrochemical performance with good lithium storage capability. Structural analyses show that Na 2 Ti 3 O 7 anode experiences slight volume change during electrochemical lithiation/delithiation process. Moreover, the reversibility of structural evolution is further demonstrated by in-situ X-ray diffraction technique . All these evidences prove the cycling stability of Na 2 Ti 3 O 7 as lithium storage material. Besides, the kinetic properties of the Li + ion storage in Na 2 Ti 3 O 7 are systematically investigated. The observed results reveal that Na 2 Ti 3 O 7 delivers the lithium ions diffusion coefficient in the range of 10 − 14 –10 − 12 cm 2 s − 1 during the discharge process and 10 − 15 –10 − 12 cm 2 s − 1 during the recharge process. It suggests that Na 2 Ti 3 O 7 has good lithiation/delithiation kinetics in rechargeable batteries.
研究领域:
电化学
·
材料科学
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能源存储
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无机化学
·
固体化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）