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Synthesis of NaY zeolite from a submolten depolymerized perlite:Alkalinity effect and crystallization kinetics

Chinese Journal of Chemical Engineering 2024年第6期70卷 130-138页

作者： Yanli Qu Peng Dong Li Yang Yuanyuan Yue Haoliang Wang Jingcai Cheng Chao Yang cas Key Laboratory of Green Process and Engineering State Key Laboratory of Petroleum Molecular&Process EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100190China Qingyuan Innovation Laboratory Quanzhou 362801China National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350108China

NaY zeolites are synthesized using submolten salt depolymerized natural perlite mineral as the main silica and alumina sources in a 0.94 L stirred *** of alkalinity ranging from 0.38 to 0.55(n(Na_(2)O)/n(SiO_(2)))on the relative crystallinity,textural properties and crystallization kinetics were *** results show that alkalinity exerts a nonmonotonic influence on the relative crystallinity and textural properties,which exhibit a maximum at the alkalinity of *** nucleation kinetics are studied by fitting the experimental data of relative crystallinity with the Gualtieri *** is shown that the nucleation rate constant increases with increasing alkalinity,while the duration period of nucleation decreases with increasing *** n(Na_(2)O)/n(SiO_(2))ratios ranging from 0.38 to 0.55,the as-synthesized NaY zeolites exhibit narrower crystal size distributions with the increase in *** growth rates determined from the variations of average crystal size with time are 51.09,157.50,46.17 and 24.75 nm·h^(-1),*** is found that the larger average crystal sizes at the alkalinity of 0.38 and 0.43 are attributed to the dominant role of crystal growth over ***,the combined action of prominent crystal growth and the longer duration periods of nucleation at the alkalinity of 0.38 and 0.43 results in broader crystal size *** findings demonstrate that control of the properties of NaY zeolite and the crystallization kinetics can be achieved by conducting the crystallization process in an appropriate range of alkalinity of the reaction mixture.

关键词： NaY zeolite Submolten salt depolymerized perlite Alkalinity Crystallization kinetics

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THE ABRUPT CHANGE OF TROPICAL CYCLONE NUMBER OVER THE WESTERN NORTH PACIFIC IN THE MID-1990s

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Journal of Tropical Meteorology 2017年第3期23卷 323-333页

作者： LI De-lin XIAO Zi-niu XIN Fei ZHOU Xiu-hua State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Shanghai Climate Center Shanghai 200030 China Guangxi Climate Center Nanning 530022 China

Based on the CMA tropical cyclone(TC) best track data as well as the reanalysis datasets from the NCEP/NCAR and NOAA, the variation characteristics of TC number from 1949 to 2013 over the western North Pacific(including the South China Sea) are examined. Notably, the time series of TC number exhibits a significant abrupt change from more to less around 1995. Comparative analysis indicates that the environmental factors necessary to TC formation also change significantly around the mid-1990 s. After 1995, accompanying with anomalous warm sea surface temperature(SST) in western equatorial Pacific, a La Nia-like pattern in tropical Pacific appears obviously. However,compared with the period before 1995, the vertical upward movement decreases, vertical shear of tropospheric zonal wind increases, and sea level pressure(SLP) rises, all of which are unfavorable to TC formation and work together to make TC number reduce markedly after 1995. Furthermore, when the typical interannual more and less TCs years are selected in the two separate stages before and after 1995, the relative importance of oceanic and atmospheric environments in interannual TC generation is also investigated respectively. The results imply that the SST over the tropical Pacific exerts relatively important influence on TC formation before 1995 whereas the atmospheric circulation plays a more prominent role in the generation of TC after 1995.

关键词： tropical cyclone abrupt change sea surface temperature atmospheric circulation

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To perceive a perfect Dora Maar in peripheral vision

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Science China(Life Sciences) 2016年第6期59卷 640-642页

作者： Rong-Ding He Tao Su Yang Yang Ying Liu Yan Wei Rong-Qiao He Fine Art College Chengdu University State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences

The Portrait of Dora Maar（92 cm×65 cm）painted by Pablo Picasso（1937）is an aesthetic masterpiece in the world（Brigitte,1996）.Picasso paints Dora seating on a chair in frontal view with an off-set profile and disjunctive facial features（André,1976）：that is,Dora’s nose becomes an extension of her face on which the＂far＂eye is seen looking straight at *** did Picasso paint his lover Dora in such a tortured style？

关键词： perfect straight masterpiece facial chair looking frontal aesthetic Figure lover

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Trace Projection Transformation： a new method for measurement of debris flow surface velocity fields

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Frontiers of Earth Science 2016年第4期10卷 761-771页

作者： Yan YAN Peng CUI Xiaojun GUO Yonggang GE Key Laboratory of Mountain Surface Process and Hazards/Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences Beijing 100101 China

Spatiotemporal variation of velocity is impor- tant for debris flow dynamics. This paper presents a new method, the trace projection transformation, for accurate, non-contact measurement of a debris-flow surface velocity field based on a combination of dense optical flow and perspective projection transformation. The algorithm for interpreting and processing is implemented in C ＋＋ and realized in Visual Studio 2012. The method allows quantitative analysis of flow motion through videos from various angles （camera positioned at the opposite direction of fluid motion）. It yields the spatiotemporal distribution of surface velocity field at pixel level and thus provides a quantitative description of the surface processes. The trace projection transformation is superior to conventional measurement methods in that it obtains the full surface velocity field by computing the optical flow of all pixels. The result achieves a 90% accuracy of when comparing with the observed values. As a case study, the method is applied to the quantitative analysis of surface velocity field of a specific debris flow.

关键词： debris flow surface velocity field spatiotem-poral variation dense optical flow perspective projectiontransformation

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Generation of strong magnetic fields with a laser-driven coil

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High Power Laser Science and Engineering 2018年第3期6卷 1-8页

作者： Zhe Zhang Baojun Zhu Yutong Li Weiman Jiang Dawei Yuan Huigang Wei Guiyun Liang Feilu Wang Gang Zhao Jiayong Zhong Bo Han Neng Hua Baoqiang Zhu Jianqiang Zhu Chen Wang Zhiheng Fang Jie Zhang Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Collaborative Innovation Center oflFSA (CICIFSA) Shanghai Jiao Tong University Shanghai 200240 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Department of Astronomy Beijing Normal University Beijing 100875 China National Laboratory on High Power Laser and Physics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Laser Plasma Shanghai 201800 China Key Laboratory for Laser Plasmas (MoE) and Department of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240 China

As a promising new way to generate a controllable strong magnetic field, laser-driven magnetic coils have attracted interest in many research fields. In 2013, a kilotesla level magnetic field was achieved at the Gekko XII laser facility with a capacitor-coil target. A similar approach has been adopted in a number of laboratories, with a variety of targets of different shapes. The peak strength of the magnetic field varies from a few tesla to kilotesla, with different spatio- temporal ranges. The differences are determined by the target geometry and the parameters of the incident laser. Here we present a review of the results of recent experimental studies of laser-driven magnetic field generation, as well as a discussion of the diagnostic techniques required for such rapidly changing magnetic fields. As an extension of the magnetic field generation, some applications are discussed.

关键词： lab astrophysics laser-plasma interaction magnetic field plasma astrophysics

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Ethanol catalytic deposition of MoS2 on tapered fiber

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Photonics Research 2015年第3期3卷 102-107页

作者： Hao Wang Bohua Chen Xiaoyan Zhang Sheng Liu Bangqi Zhu Jun Wang Kan Wu Jianping Chen State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Materials for High-Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China

Deposition of two-dimensional（2D） MoS2 materials on the tapered fiber allows various photonic applications including saturable absorbers and four-wave *** catalytic deposition（ECD） of MoS2 on the optical tapered fiber was proposed and demonstrated in this *** from the conventional optical driven deposition using water or organic solvent,the ECD method utilized the high volatility of the ethanol solvent,which significantly increased the movement speed of the MoS2 nanosheets and thus boosted the deposition rate and reduced the minimum power threshold to drive the *** believe the ECD method should be able to be applied to other similar 2D materials such as other types of transition metal chalcogenides.

关键词： Mo than rate Ethanol catalytic deposition of MoS2 on tapered fiber EDFA

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Improving the performance of arylamine-based hole transporting materials in perovskite solar cells： Extending π-conjugation length or increasing the number of side groups？

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Journal of Energy Chemistry 2018年第5期27卷 1409-1414页

作者： Xuepeng Liu Fantai Kong Wangchao Chen Ting Yu Yin Huang Tasawar Hayat Ahmed Alsaedi Hongxia Wang Jian Chen Songyuan Dai Key Laboratory of Photovolatic and Energy Conservation Materials CAS Institute of Applied Technology Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 230088 Anhui China University of Science and Technology of China Hefei 230026 Anhui China NAAM Research Group. Department of Mathematics Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia School of Chemistry Physics and Mechanical Engineering. Queensland University of Technology Brisbane OLD 4001 Australia Beijing Key Laboratory of Novel Thin-Film Solar Cells. North China Electric Power University. Beijing 102206 China

In this work, we prepared three simple arylamine-based hole transporting materials from commercially available starting materials. The effect of extending z-conjugation length or increasing the number of side groups compared with reference compound on the photophysical, electrochemical, hole mobility properties and performance in perovskite solar cells were further studied. It is noted that these two kinds of molecular modifications can significantly lower the HOMO level and improve the hole mobility, thus improving the hole injection from valence band of perovskite. On the other hand, the compound with more side groups showed higher hole injection efficiency due to lower HOMO level and higher hole mo- bility compared with the compound with extending π-conjugation length. The perovskite solar cells with the modified molecules as hole transporting materials showed a higher efficiency of 15.40% and 16.95%, respectively, which is better than that of the reference compound （13.18%）. Moreover, the compound with increasing number of side groups based devices showed comparable photovoltaic performance with that of conventional spiro-OMeTAD （16.87%）.

关键词： Hole transporting materials Perovskite π-conjugation length Side groups

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Enhanced O2 reduction on atomically thin Pt-based nanoshells by integrating surface facet, interfacial electronic, and substrate stabilization effects

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Nano Research 2018年第6期11卷 3313-3326页

作者： Wei Ye Zhongti Sun Chengming Wang Mengshan Ye Chenhao Ren Ran Long Xusheng Zheng Junfa Zhu Xiaojun Wu Yujie Xiong Hefei National Laboratory for Physical Sciences at the Microscale iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Synergetic Innovation of Quantum Information & Quantum Technology School of Chemistry and Materials Science CAS Center for Excellence in Nanoscience and National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026 China

To fully realize the commercial viability of Pt in fuel cells, the usage of scarce Pt must be reduced while the activity and durability in 02 reduction reaction （ORR） must be enhanced. Here we report a metallic stack design achieving these goals for ORR, based on atomically precise materials synthesis. Au@Pd@Pt nanostructures with atomically thin Pt shells and high-index surfaces form an excellent platform for integrating the effects of electronic structures, surface facets, and substrate stabilization to boost ORR performance. Au@Pd@Pt trisoctahedrons （TOH） achieve mass activity 6.1 times higher than that of commercial Pt/C and dramatically enhanced durability beyond 1.0 V vs. a reversible hydrogen electrode in oxidation potential. Meanwhile, Pt comprises only 3.2% of the nanostructures. To further improve the ORR activity and demonstrate the versatility of our strategy, we implement the same design in PtNi alloy electrocatalysts. The Au@Pd@PtNi TOHs exhibit mass activity 14.3 times higher than that of commercial Pt/C as well as excellent durability. This work demonstrates an alternative strategy for fabricating high-performance and low-cost catalysts, and highlights the importance of simultaneous surface and interfacial engineering with atomic precision in designing catalysts.

关键词： oxygen reduction reaction electrocatalysis interfacial electronic effect surface facet substrate stabilization Pt

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Evaluation of CORDEX regional climate models in simulating temperature and precipitation over the Tibetan Plateau

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Atmospheric and Oceanic Science Letters 2018年第3期11卷 219-227页

作者： GUO Dong-Lin SUN Jian-Qi YU En-Tao Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of Sciences Key Laboratory of Meteorological Disaster Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science & Technology Joint Laboratory for Climate and Environmental Change Chengdu University of Information Technology

Using a regional climate model（RCM） is generally regarded as a promising approach in researching the climate of the Tibetan Plateau, due to the advantages provided by the high resolutions of these models. Whilst previous studies have focused mostly on individual RCM simulations, here, multiple RCMs from the Coordinated Regional Climate Downscaling Experiment are evaluated in simulating surface air temperature and precipitation changes over the Tibetan Plateau using station and gridded observations. The results show the following：（1） All RCMs consistently show similar spatial patterns, but a mean cold（wet） bias in the temperature（precipitation） climatology compared to station observations. The RCMs fail to reproduce the observed spatial patterns of temperature and precipitation trends, and on average produce greater trends in temperature and smaller trends in precipitation than observed results. The multi-model ensemble overall produces superior trends in both simulated temperature and precipitation relative to individual models. Meanwhile, Reg CM4 presents the most reasonable simulated trends among the five RCMs.（2） Considerable dissimilarities are shown in the simulated quantitative results from the different RCMs, which indicates a large model dependency in the simulation of climate over the Tibetan Plateau. This implies that caution may be needed when an individual RCM is used to estimate the amplitude of climate change over the Tibetan Plateau.（3） The temperature（precipitation） in 2016–35, relative to 1986–2005, is projected by the multi-model ensemble to increase by 1.38 ± 0.09 °C（0.8% ± 4.0%） and 1.77 ± 0.28 °C（7.3% ± 2.5%） under the RCP4.5 and RCP8.5 scenario, respectively. The results of this study advance our understanding of the applicability of RCMs in studies of climate change over the Tibetan Plateau from a multiple-RCM perspective.

关键词： Tibetan Plateau RCM climate simulation CORDEX

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Tunable nonlinear refractive index of two-dimensional MoS2, WS2, and MoSe2 nanosheet dispersions [Invited]

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Photonics Research 2015年第2期3卷 51-55页

作者： Gaozhong Wang Saifeng Zhang Xiaoyan Zhang Long Zhang Ya Cheng Daniel Fox Hongzhou Zhang Jonathan N.Coleman Werner J.Blau Jun Wang Key Laboratory of Materials for High-Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences School of Physics and the Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) Trinity College Dublin State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences

Liquid-phase-exfoliation technology was utilized to prepare layered MoS2, WS2, and MoSe2 nanosheets in cyclohexylpyrrolidone. The nonlinear optical response of these nanosheets in dispersions was investigated by observing spatial self-phase modulation（SSPM） using a 488 nm continuous wave laser beam. The diffraction ring patterns of SSPM were found to be distorted along the vertical direction right after the laser traversing the nanosheet dispersions. The nonlinear refractive index of the three transition metal dichalcogenides dispersions n2 was measured to be 10-7cm2W-1, and the third-order nonlinear susceptibility χ（3）10-9 esu. The relative change of effective nonlinear refractive index Δn2e∕n（2e） of the MoS2, WS2, and MoSe2 dispersions can be modulated 0.012–0.240, 0.029–0.154, and 0.091–0.304, respectively, by changing the incident intensities. Our experimental results imply novel potential application of two-dimensional transition metal dichalcogenides in nonlinear phase modulation devices.

关键词： Mo show exp Tunable nonlinear refractive index of two-dimensional MoS2 WS2

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