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453 results on '"Zhu, Qingjun"'

107. Conceptual design of the supercritical CO2 cooled lithium lead blanket for CFETR

Author

Qiuran Wu, Nian-Mei Zhang, Jiang Kecheng, Long Chen, Songlin Liu, Juan-Cheng Yang, Ming-Jiu Ni, Chen Lei, Zhu Qingjun, Yi Yu, Huang Kai, Xiaoman Cheng, Peng Lu, and Xuebin Ma

Subjects
Thermal efficiency, Neutron transport, Mechanical Engineering, Nuclear engineering, chemistry.chemical_element, Blanket, Fusion power, Turbine, Supercritical fluid, Nuclear Energy and Engineering, chemistry, Conceptual design, Environmental science, General Materials Science, Lithium, Civil and Structural Engineering
Abstract

A conceptual design of the supercritical CO2 cOoled Lithium-Lead (COOL) blanket has been proposed as one advanced blanket candidate for the Chinese Fusion Engineering Testing Reactor (CFETR). At present, the COOL blanket is designed to fulfill the requirement of operating under the fusion power of 1.5 GW of CFETR while realizing the tritium self-sufficiency. Structural designs are carried out for outboard and inboard blanket segments and analyses with regard to neutronics and thermo-hydraulics are conducted to evaluate the blanket performance. Results indicate that a comparatively high Tritium Breeding Ratio (TBR) of 1.183 and a PbLi outlet temperature of 600 – 700°C can be achieved for this blanket concept. Besides, a Power Conversion System (PCS) based on the supercritical CO2 recompressing cycle is preliminarily designed for the blanket and the gross thermal efficiency is estimated to be 39% – 46% when assuming the turbine inlet temperature ranges between 550°C and 650°C.

Published
2021

115. Neutronics assessments of LHCD antenna system for CFETR

Author

Yu Zheng, Hua Du, Songlin Liu, Zhu Qingjun, Qiuran Wu, Liang Liu, and Peng Lu

Subjects
Neutron transport, Materials science, Mechanical Engineering, Nuclear engineering, Nuclear data, Blanket, Fusion power, Front and back ends, Nuclear Energy and Engineering, Electromagnetic shielding, General Materials Science, Neutron, Antenna (radio), Civil and Structural Engineering
Abstract

To maintain a long-duration plasma current and obtain steady-state operation for CFETR, a non-inductive Heating and Current Drive (H&CD) system is currently under study. Lower Hybrid Current Drive (LHCD) is an important auxiliary heating system, that has good current drive efficiency and improves plasma confinement by changing the current distribution. Neutronics calculation was conducted to study the nuclear performance and shielding effectiveness. This study was performed on a CFETR 22.5° model integrated with an upper-port LHCD antenna structure. The detailed 3D neutronics model was built using the computer-aided modeling platform cosVMPT, and particle transport was performed using MCNP5 with the nuclear data library FENDL-2.1. With the support of high performance variance reduction technique, “on-the-fly” GVR method, global neutron and photon flux distributions with reasonable relative error were obtained. The irradiation damage to components in the antenna system was assessed, including DPA, gas production and nuclear heat density. The total nuclear heat for the transmission structure was 1.192 MW, and the peak irradiation damage was located at the front end of the Passive-Active Multi-junction (PAM) launcher. Owing to the blanket opening for wave propagation, the induced nuclear responses for VV and TFC were analyzed, and the shielding design was initialized. The results showed that all the parameters were within the design limit after the shielding design. Because part of the blanket module was occupied by the antenna launcher, the TBR of CFETR was evaluated, and it decreased by only 0.22% for the whole fusion reactor.

Published
2021

117. On the Activity/Selectivity and Phase Stability of Thermally Grown Copper Oxides during the Electrocatalytic Reduction of CO2

Author

Velasco-Vélez, Juan-Jesús, primary, Chuang, Cheng-Hao, additional, Gao, Dunfeng, additional, Zhu, Qingjun, additional, Ivanov, Danail, additional, Jeon, Hyo Sang, additional, Arrigo, Rosa, additional, Mom, Rik Valentijn, additional, Stotz, Eugen, additional, Wu, Heng-Liang, additional, Jones, Travis E., additional, Roldan Cuenya, Beatriz, additional, Knop-Gericke, Axel, additional, and Schlögl, Robert, additional

Published
2020
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120. Unusual Thermal Properties of Certain Poly(3,5-disubstituted styrene)s

Author

Koh, Jai Hyun, primary, Zhu, Qingjun, additional, Asano, Yusuke, additional, Maher, Michael J., additional, Ha, Heonjoo, additional, Kim, Sung-Soo, additional, Cater, Henry L., additional, Mapesa, Emmanuel U., additional, Sangoro, Joshua R., additional, Ellison, Christopher J., additional, Lynd, Nathaniel A., additional, and Willson, C. Grant, additional

Published
2020
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124. Activation of Telomerase by Human Cytomegalovirus

Author

Strååt, Klas, Liu, Cheng, Rahbar, Afsar, Zhu, Qingjun, Liu, Li, Wolmer-Solberg, Nina, Lou, Fenglan, Liu, Zhaoxu, Shen, Jie, Jia, Jihui, Kyo, Satoru, Björkholm, Magnus, Sjöberg, Jan, Söderberg-Nauclér, Cecilia, and Xu, Dawei

Published
2009

125. Neutronics Analysis of Water-Cooled Ceramic Breeder Blanket for CFETR

Author

Li Jia, Zhu Qingjun, and Liu Songlin

Subjects
010302 applied physics, Neutron transport, Materials science, Nuclear engineering, Divertor, Nuclear data, Blanket, Fusion power, Condensed Matter Physics, 01 natural sciences, 010305 fluids & plasmas, Breeder (animal), visual_art, 0103 physical sciences, visual_art.visual_art_medium, Neutron, Ceramic, Nuclear Experiment
Abstract

In order to investigate the nuclear response to the water-cooled ceramic breeder blanket models for CFETR, a detailed 3D neutronics model with 22.5° torus sector was developed based on the integrated geometry of CFETR, including heterogeneous WCCB blanket models, shield, divertor, vacuum vessel, toroidal and poloidal magnets, and ports. Using the Monte Carlo N-Particle Transport Code MCNP5 and IAEA Fusion Evaluated Nuclear Data Library FENDL2.1, the neutronics analyses were performed. The neutron wall loading, tritium breeding ratio, the nuclear heating, neutron-induced atomic displacement damage, and gas production were determined. The results indicate that the global TBR of no less than 1.2 will be a big challenge for the water-cooled ceramic breeder blanket for CFETR.

Published
2016

128. In situ X-ray Spectroscopy Investigation of the Cathodic Electroreduction of CO2 into Valuable Chemical Feedstocks onto Copper Based Catalysts

Author

Velasco Vélez, Juan J., primary, Chuang, Cheng-Hao, additional, Gao, Dunfeng, additional, Zhu, Qingjun, additional, Jones, Travis, additional, Carbonio, Emilia, additional, Strasser, Peter, additional, Roldán-Cuenya, Beatriz, additional, Schlögl, Robert, additional, and Knop-Gericke, Axel, additional

Published
2019
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132. Redox transients of P680 associated with the incremental chlorophyll‐a fluorescence yield rises elicited by a series of saturating flashes in diuron‐treated photosystem II core complex of Thermosynechococcus vulcanus

Author

Sipka, Gábor, primary, Müller, Pavel, additional, Brettel, Klaus, additional, Magyar, Melinda, additional, Kovács, László, additional, Zhu, Qingjun, additional, Xiao, Yanan, additional, Han, Guangye, additional, Lambrev, Petar H., additional, Shen, Jian‐Ren, additional, and Garab, Győző, additional

Published
2019
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137. An Optimized Method for Bonner Sphere Spectrometer Design and Validation by Measuring 252Cf Spectra.

Author

Zhu, Qingjun, Meng, Xianfang, Chen, Wuhui, Liu, Songlin, and Huang, Kai

Abstract

A methodology for designing a Bonner sphere spectrometer was proposed based on the singular value decomposition (SVD) and information entropy theory. First, features of Bonner spheres were classified based on SVD, and then, the rationality of the selected spheres was analyzed. Second, the information entropy is used as the quantitative evaluation standard; combined with the unfolding method, the contribution of each Bonner sphere on the information entropy of the unfolded spectra was quantitatively analyzed. The spheres that have high influence on the information entropy of solution spectra can be identified, and then, the information entropy variation of the solution spectra can be suppressed by reducing the count fluctuation of these spheres. According to the proposed method, an optimized spectrometer was developed and applied to measuring 252Cf spectra. [ABSTRACT FROM AUTHOR]

Published
2021
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139. Review and Perspectives of the In SituModification Strategy for Bifunctional Electrodes in a Vanadium Redox Flow Battery

Author

Xiao, Yanna, Yuan, Caiyue, Fan, Weijia, Wang, Yinhui, Li, Yuan, Feng, Zemin, Qi, Shaotian, Jiang, Yingqiao, Li, Yuehua, Zhu, Qingjun, Dai, Lei, and He, Zhangxing

Abstract

A vanadium redox flow battery (VRFB) represents the most commercially advanced and mature technology among redox flow batteries presently available. However, the catalytic activity of the original electrode material significantly hinders the energy efficiency of the vanadium ion redox reactions. Therefore, improving the electrodes is imperative to enhance the performance of the battery. VRFB commercialization is facilitated by the utilization of bifunctional electrodes acquired through in situmodification techniques. This approach enhances the performance of both the positive and negative electrodes, thereby increasing the efficiency of the battery. This study provides a summary of research concerning bifunctional electrodes acquired through in situmodification, including acid treatment, electrochemical treatment, heat treatment, and some novel methods. Furthermore, the application and challenges associated with bifunctional electrodes in VRFB are also outlined. This review concludes with a perspective on the future trajectory of VRFB development, elucidating the direction of its commercial advancement.

Published
2024
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140. Engineering Interface with One-Dimensional Co3O4Nanostructure in Catalytic Membrane Electrode: Toward an Advanced Electrocatalyst for Alcohol Oxidation

Author

Yin, Zhen, Zheng, Yumei, Wang, Hong, Li, Jianxin, Zhu, Qingjun, Wang, Ye, Ma, Na, Hu, Gang, He, Benqiao, Knop-Gericke, Axel, Schlögl, Robert, and Ma, Ding

Abstract

Electrochemical oxidation has attracted vast interest as a promising alternative to traditional chemical processes in fine chemical synthesis owing to its fast and sustainable features. An electrocatalytic membrane reactor (ECMR) with a three-dimensional (3D) electrode has been successfully designed for the selective oxidation of alcohols with high current efficiency to the corresponding acids or ketones. The anode electrode was fabricated by the in situloading of one-dimensional (1D) Co3O4nanowires (NWs) on the conductive porous Ti membrane (Co3O4NWs/Ti) viathe combination of a facile hydrothermal synthesis and subsequent thermal treatment. The electrocatalytic oxidation (ECO) results of alcohols exhibited superior catalytic performance with a higher current efficiency on the Co3O4NWs/Ti membrane compared with those of Co3O4nanoparticles on the Ti membrane (Co3O4NPs/Ti). Even under low reaction temperatures such as 0 °C, it still displayed a very high ECO activity for alcohol oxidation in the ECMR. For example, >99% conversion and 92% selectivity toward benzoic acid were obtained for the benzyl alcohol electrooxidation. The electrode is particularly effective for the cyclohexanol oxidation, and a selectivity of >99% to cyclohexanone was achieved at 0 °C, higher than most reported noble-metal catalysts under the aerobic reaction conditions. The extraordinary electrocatalytic performance of the 3D Co3O4NWs/Ti membrane electrode demonstrates the significant influence of morphology effect and engineering interfaces in membrane electrodes on the electrocatalytic activity and charge transfer process of nanocatalysts. Our results propose that similar membrane electrodes serve as versatile platforms for the applications of 1D nanomaterials, porous electrodes, and ECMRs.

Published
2024
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142. Engineering Interface with One-Dimensional Co3O4 Nanostructure in Catalytic Membrane Electrode: Toward an Advanced Electrocatalyst for Alcohol Oxidation

Author

Yin, Zhen, primary, Zheng, Yumei, additional, Wang, Hong, additional, Li, Jianxin, additional, Zhu, Qingjun, additional, Wang, Ye, additional, Ma, Na, additional, Hu, Gang, additional, He, Benqiao, additional, Knop-Gericke, Axel, additional, Schlögl, Robert, additional, and Ma, Ding, additional

Published
2017
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144. An Optimized Method for Bonner Sphere Spectrometer Design and Validation by Measuring 252Cf Spectra

Author

Zhu, Qingjun, Meng, Xianfang, Chen, Wuhui, Liu, Songlin, and Huang, Kai

Abstract

AbstractA methodology for designing a Bonner sphere spectrometer was proposed based on the singular value decomposition (SVD) and information entropy theory. First, features of Bonner spheres were classified based on SVD, and then, the rationality of the selected spheres was analyzed. Second, the information entropy is used as the quantitative evaluation standard; combined with the unfolding method, the contribution of each Bonner sphere on the information entropy of the unfolded spectra was quantitatively analyzed. The spheres that have high influence on the information entropy of solution spectra can be identified, and then, the information entropy variation of the solution spectra can be suppressed by reducing the count fluctuation of these spheres. According to the proposed method, an optimized spectrometer was developed and applied to measuring 252Cf spectra.

Published
2021
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