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1. chinaXiv:201705.00588 [pdf]

Porosity effect on ZrO2 hollow shells and hydrothermal stability for catalytic steam reforming of methane

Lim, ZY [Lim, Zi-Yian][ 2,1 ]; Wu, CZ [Wu, Chunzheng][ 1 ]; Wang, WG [Wang, Wei Guo][ 1 ]; Choy, KL [Choy, Kwang-Leong][ 3 ]; Yin, HF [Yin, Hongfeng][ 1 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

Hydrogen is an emerging energy source/carrier for oil refining and fuel cell applications. The development of an efficient and stable catalyst to produce hydrogen-rich gas is required for industrial application. The Ni@yolk-ZrO2 catalyst could be a potential solution to tackle the challenges in hydrogen production. The catalyst was characterized using a combination of XRD, TEM, AAS, TPR, BET, and XPS. In this study, the amount of micropores in ZrO2 hollow shells was demonstrated to influence the catalytic performance. Ni@yolk-ZrO2 catalysts were evaluated for 48 hours under steam reforming of methane and their porosity effect in ZrO2 hollow shells was identified. From the characterization of BET and catalytic evaluation, the physical information of the ZrO2 hollow shell was established, which affected the catalytic performance in steam reforming of methane. Furthermore, the results from XPS and TEM showed that Ni particles were controlled under a ZrO2 yolk–shell structure framework and showed the characteristic of moderately strong hydrothermal stability after the steam reforming test. The catalysts were studied at a GHSV of 50 400 mL gcat 1 h 1 and S/C 1?4 2.5 at 750 C and they remained stable with methane conversion more than 90% for 48 hours.

submitted time 2017-05-02 Hits1600Downloads578 Comment 0

2. chinaXiv:201705.00437 [pdf]

Quantitative contribution of resistance sources of components to stack performance for solid oxide electrolysis cells

Zheng, YF [Zheng, Yifeng][ 1 ]; Li, QS [Li, Qingshan][ 1 ]; Chen, T [Chen, Tao][ 1 ]; Xu, C [Xu, Cheng][ 1 ]; Wang, WG [Wang, Wei Guo][ 1 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

Quantitative investigation is conducted on the resistance sources of the components in the NiOeYSZ/ YSZ/GDC/LSCFeGDC solid oxide electrolysis cell (SOEC) stack at the H2O/H2 ratios of 70/30, 80/20 and 90/ 10 at 750 C. The results indicate that the cell resistance accounts for 76.3e66.7% of that of the stack repeating unit (SRU), the contact resistance (CR) between the air electrode current-collecting layer (AECCL) and the interconnect accounts for 23.6e27.0%, the CR between the hydrogen electrode current- collecting layer (HECCL) and the interconnect only accounts for 2.3e3.2%, and the resistance of the interconnect can be neglected. Duration test of the stack is conducted at 0.8 A cm 2 for 380 h, the cell resistance increase is found to be the major contribution of the SRU degradation (82.2% of the SRU degradation) while the air electrode CR increase and the hydrogen electrode CR increase are other two important factors.

submitted time 2017-05-02 Hits795Downloads433 Comment 0

3. chinaXiv:201705.00427 [pdf]

Synthesis, Characterization, and Catalytic Activity of Mn-doped Perovskite Oxides for Three-Way Catalysis

Zhou, C [Zhou, Chen][ 1 ]; Zhang, YX [Zhang, Yexin][ 1 ]; Hu, LJ [Hu, Lingjun][ 1 ]; Yin, HF [Yin, Hongfeng][ 1 ]; Wang, WG [Wang, Wei Guo][ 1 ]

Mn-doped La0.8Sr0.2CoO3 perovskite oxides [La0.8Sr0.2Co1-xMnxO3; x = 0, 0.1, 0.3, 0.5] were synthesized by a modified sol-gel method. The phase-pure oxides were obtained. CoO and carbonates were formed on the surface of La0.8Sr0.2CoO3. With increasing dop

submitted time 2017-05-02 Hits563Downloads336 Comment 0

4. chinaXiv:201705.00301 [pdf]

Synthesis and electrical properties of screen-printed doped ceria interlayer for IT-SOFC applications

Sun, JL [Sun, Jia Long][ 1 ]; Wang, JX [Wang, Jian Xin][ 1 ]; He, CR [He, Chang Rong][ 1 ]; Shen, P [Shen, Pin][ 1 ]; Wang, Q [Wang, Qin][ 2 ]; Miao, H [Miao, He][ 1 ]; Wang, WG [Wang, Wei Guo][ 1 ]

In this paper, four types of doped ceria powders and sinters, including Gd0.1Ce0.9O1.95, Gd0.2Ce0.8O1.9, Sm0.1Ce0.9O1.95 and Sm0.2Ce0.8O1.9, are prepared and characterized. The results indicate that the Sm0.2Ce0.8O1.9 samples possess the lowest densificat

submitted time 2017-05-02 Hits618Downloads381 Comment 0

5. chinaXiv:201703.01020 [pdf]

Selective and recyclable palladium porphyrins-catalyzed oligomerization of tert-butyl acetylene in environment-friendly ionic liquids

Cheng, Jin-Sheng; Wei, Guo-Feng; Zhao, Jin; Huang, Shi-Wen; Huang, Zu-Liang
Subjects: Biology >> Biomedical Laboratory Science

Efficient and selective palladium porphyrins-catalyzed olimerization of tert-butyl acetylene to form (3Z,5Z)-2,2,7,7-tetramethyl-3,6-dihalo-3,5-octadiene has been developed in environmentfriendly ionic liquids. The reaction proceeded readily with effective recycling of the ionic liquids and easy isolation of the products.

submitted time 2017-03-30 Hits2575Downloads993 Comment 0

6. chinaXiv:201612.00205 [pdf]

HY-2A Radar Altimeter Ultra Stable Oscillator Drift Estimation using Reconstructive Transponder with its Validation by Multi-mission Cross-Calibration

Junzhi Wan; Wei Guo; Fei Zhao; Caiyun Wang; Peng Liu
Subjects: Geosciences >> Space Physics

The paper presents a method estimating the HY-2A altimeter ultra stable oscillator (USO) drift with a reconstructive transponder. The frequency of the USO of the in-orbit altimeter changes with age, and a bias between the actual frequency and the nominal one exists. The USO bias contributes a portion of the altimeter range drift. The HY-2A altimeter transmits signals at a fixed time interval during calibration, and the actual interval between adjacent altimeter transitions, which is controlled by the USO, is different from the nominal one due to the USO drift. The reconstructive transponder measures the arrival times of the altimeter transmitted signals accurately with the atomic clock. The drift of the USO on-board the HY-2A altimeter can be estimated accurately by using the ranges from the reconstructive transponder and the HY-2A altimeter. The USO drifts of around 40 cm/year are presented. Furthermore, the multi-mission crosscalibration provides preliminary validation of HY-2A altimeter USO drift.

submitted time 2016-12-26 Hits2341Downloads881 Comment 0

7. chinaXiv:201612.00202 [pdf]

HY-2A Altimeter Time Tag Bias Estimation Using Reconstructive Transponder

Junzhi Wan; Wei Guo; Fei Zhao; Caiyun Wang
Subjects: Geosciences >> Space Physics

Independent clocks provide time tags for the precision orbit determination (POD) equipment and the radar altimeter onboard the HY-2A satellite, and a bias between POD data' time tag and corresponding range observation's time tag from the HY-2A altimeter exists. The time tag bias contributes a bias in the sea surface height observation due to the nonzero time rate of change of the HY-2A altimeter's height. A transponder for in-orbit radar altimeter calibration provides an approach to estimate the time tag bias. The altimeter receives the responding signals from the transponder and generates ranges. Pertinent reference ranges are obtained fromthe POD data and the transponder's coordinate. Using the ranges from the radar altimeter and the reference ranges, the time tag bias between the POD data and the altimeter observations can be estimated. During an in situ HY-2A altimeter calibration campaign using a reconstructive transponder from August 9, 2012, to July 20, 2014, 17 estimations of the altimeter's time tag bias were obtained. The preliminary results are presented in this letter.

submitted time 2016-12-26 Hits2231Downloads889 Comment 0

8. chinaXiv:201612.00199 [pdf]

Echo Signal Quality Analysis During HY-2A Radar Altimeter Calibration Campaign Using Reconstructive Transponder

Junzhi Wan; Wei Guo; Fei Zhao; Caiyun Wang; Peng Liu; Mingsen Lin; Hailong Peng; Chuan Xu
Subjects: Geosciences >> Space Physics

A reconstructive transponder has been utilized for the in-orbit calibration campaign of the HY-2A radar altimeter since March 2012. The precision of final calibration result is influenced by echo signal's quality in the HY-2A altimeter's range window. As an indicator of the signal's quality, echo signal dwell time is analyzed considering its influence on signal quality and its uncertainty. In HY-2A altimeter calibration, the echo signal dwell time is determined by the radial orbit prediction uncertainty and the real-time signal processing mechanism of the reconstructive transponder. The real-time signal processing mechanism of the reconstructive transponder utilizes some incoming signal samples without sending echo signals before transmitting. Comparing with the length of the HY-2A altimeter's range window, the radial orbit prediction uncertainty is large. Large radial orbit prediction uncertainty and signal processing mechanism of the reconstructive transponder are two main factors that limit the echo signal dwell time in HY-2A altimeter calibration. Finally, approaches for increasing echo signal dwell time are briefly proposed.

submitted time 2016-12-26 Hits2380Downloads817 Comment 0

9. chinaXiv:201612.00197 [pdf]

A Matching Method for Establishing Correspondence between Satellite Radar Altimeter Data and Transponder Data Generated during Calibration

Junzhi Wan; Wei Guo; Caiyun Wang; Fei Zhao
Subjects: Geosciences >> Space Physics

This letter presents a method for matching satellite radar altimeter data and transponder data generated during in situ calibration. The transponder generates a measurement error when it measures the arrival time of the altimeter’s transmitted signal and embeds the error in both the transponder’s recorded data and the altimeter’s recorded data. The secondorder finite difference sequence of this error sequence can be extracted from the raw data, thus, the correspondence between two identical but mismatched second-order difference sequences can be uniquely established. The measurement error is utilized,and a data matching method that can uniquely establish the correspondence between the altimeter’s recorded data sequence and the transponder’s recorded data sequence is presented.This post-processing method does not increase the real-time signal processing workload of the transponder. Furthermore,The principles underlying this method can be used for any transponder that can adjust the response signal delay during calibration.

submitted time 2016-12-26 Hits1876Downloads730 Comment 0

10. chinaXiv:201609.00906 [pdf]

Study of cluster reconstruction and track fitting algorithms for CGEM-IT at BESIII

GUO Yue; WANG Liang-Liang; JU Xu-Dong; WU Ling-Hui; XIU Qing-Lei; WANG Hai-Xia; DONG Ming-Yi; HU Jing-Ran; LI Wei-Dong; LI Wei-Guo; LIU Huai-Min; OU-YANG Qun; SHEN Xiao-Yan; YUAN Ye; ZHANG Yao
Subjects: Physics >> Nuclear Physics

Considering the aging effects of existing Inner Drift Chamber (IDC) of BES\uppercase\expandafter{\romannumeral3}, a GEM based inner tracker is proposed to be designed and constructed as an upgrade candidate for IDC. This paper introduces a full simulation package of CGEM-IT with a simplified digitization model, describes the development of the softwares for cluster reconstruction and track fitting algorithm based on Kalman filter method for CGEM-IT. Preliminary results from the reconstruction algorithms are obtained using a Monte Carlo sample of single muon events in CGEM-IT.

submitted time 2016-09-13 Hits1020Downloads562 Comment 0

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