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Estimating the thickness of diffusive solid electrolyte interface

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Science China(Physics,Mechanics & Astronomy) 2017年第6期60卷 61-68页

作者： XiaoHe Wang WenHao Shen XianFu Huang JinLiang Zang YaPu Zhao State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

electrolyte. The properties of lithium-ion (Li-ion) battery, such as cycle life, irreversible capacity loss, self-discharge rate, electrode corrosion and safety are usually ascribed to the quality of the SEI, which are highly dependent on the thickness. Thus, understanding the formation mechanism and the SEI thickness is of prime interest. First, we apply dimensional analysis to obtain an explicit relation between the thickness and the number density in this study. Then the SEI thickness in the initial charge-discharge cycle is analyzed and estimated for the first time using the Cahn-Hilliard phase-field model. In addition, the SEI thickness by molecular dynamics simulation validates the theoretical results. It has been shown that the established model and the simulation in this paper estimate the SEI thickness concisely within order-of-magnitude of nanometers. Our results may help in evaluating the performance of SEI and assist the future design of Li-ion battery.

关键词： lithium-ion battery solid electrolyte interface diffusion model thickness estimation

Efects of physical and chemical characteristics of surface sediments in the formation of shallow lake algae-induced black bloom

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Journal of Environmental sciences 2013年第12期25卷 2353-2360页

作者： Qiushi Shen Cheng Liu Qilin Zhou Jingge Shang Lei Zhang ChengXin Fan University of Chinese academy of sciences State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences

Surface sediments are closely related to lake black blooms. The dissolved oxygen （DO） distribution and its penetration depth in surface sediments as well as the migration and transformation of redox sensitive elements such as Fe and S at the sediment-water interface are important factors that could influence the formation of the black bloom. In this study, dredged and undredged sediment cores with different surface properties were used to simulate black blooms in the laboratory. The Micro Profiling System was employed to explore features of the DO and ∑H2S distribution at the sediment-water interface. Physical and chemical characteristics in sediments and pore waters were also analyzed. The results showed that sediment dredging effectively suppressed the black blooms. In the undredged treatment, DO penetration depth was only 50 μm. Fe^2＋ concentrations, ∑H2S concentrations, and ∑H2S production rates were remarkably higher in surface sediments and pore waters compared to control and dredged treatments. Furthermore, depletion of DO and accumulation of Fe^2＋ and ∑H2S in surface sediments and pore waters provided favorable redox environments and necessary material sources for the blooms. The study results proved that physical and chemical characteristics in surface sediments are important factors in the formation of the black bloom, and could provide scientific guidance for emergency treatment and long-term pre-control of black blooms.

关键词： black bloom sediment-water interface dredging sediment micro interface lake

The role of initial signals in the tropical Pacific Ocean in predictions of negative Indian Ocean Dipole events

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Science China Earth sciences 2018年第12期61卷 1832-1843页

作者： Rong FENG Wansuo DUAN LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese academy of sciences Beijing 100049China

Using reanalysis data, the role of initial signals in the tropical Pacific Ocean in predictions of negative Indian Ocean Dipole(IOD) events were analyzed. It was found that the summer predictability barrier(SPB) phenomenon exists in predictions,which is closely related to initial sea temperature errors in the tropical Pacific Ocean, with type-1 initial errors presenting a significant west-east dipole pattern in the tropical Pacific Ocean, and type-2 initial errors showing the opposite spatial pattern. In contrast, SPB-related initial sea temperature errors in the tropical Indian Ocean are relatively small. The initial errors in the tropical Pacific Ocean induce anomalous winds in the tropical Indian Ocean by modulating the Walker circulation in the tropical oceans. In the first half of the prediction year, the anomalous winds, combined with the climatological winds in the tropical Indian Ocean, induce a basin-wide mode of sea surface temperature(SST) errors in the tropical Indian Ocean. With the reversal of the climatological wind in the second half of the prediction year, a west-east dipole pattern of SSTerrors appears in the tropical Indian Ocean, which is further strengthened under the Bjerknes feedback, yielding a significant SPB. Moreover, two types of precursors were also identified: a significant west-east dipole pattern in the tropical Pacific Ocean and relatively small temperature anomalies in the tropical Indian Ocean. Under the combined effects of temperature anomalies in the tropical Indian and Pacific oceans, northwest wind anomalies appear in the tropical Indian Ocean, which induce a significant west-east dipole pattern of SST anomalies, and yield a negative IOD event.

关键词： Negative Indian Ocean Dipole Precursor Initial errors Pacific Ocean

Hg^0 removal from flue gas over different zeolites modified by Fe Cl_3

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Journal of Environmental sciences 2015年第2期27卷 110-117页

作者： Hao Qi Wenqing Xu Jian Wang Li Tong Tingyu Zhu Beijing Engineering Research Center of Process Pollution Control Institute of Process Engineering Chinese Academy of Sciences University of Chinese academy of sciences

The elemental mercury removal abilities of three different zeolites（Na A, Na X, HZSM-5）impregnated with iron（Ⅲ） chloride were studied on a lab-scale fixed-bed reactor. X-ray diffraction, nitrogen adsorption porosimetry, Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy, and temperature programmed desorption（TPD） analyses were used to investigate the physicochemical properties. Results indicated that the pore structure and active chloride species on the surface of the samples are the key factors for physisorption and oxidation of Hg0, respectively. Relatively high surface area and micropore volume are beneficial to efficient mercury adsorption. The active Cl species generated on the surface of the samples were effective oxidants able to convert elemental mercury（Hg0）into oxidized mercury（Hg2＋）. The crystallization of Na Cl due to the ion exchange effect during the impregnation of Na A and Na X reduced the number of active Cl species on the surface, and restricted the physisorption of Hg0. Therefore, the Hg0 removal efficiencies of the samples were inhibited. The TPD analysis revealed that the species of mercury on the surface of Fe Cl3–HZSM-5 was mainly in the form of mercuric chloride（Hg Cl2）, while on Fe Cl3–Na X and Fe Cl3–Na A it was mainly mercuric oxide（HgO）.

关键词： Mercury Zeolite Flue gas Adsorption Iron chloride HZSM-5

Preliminary result of bunch length measurement using a modified Michelson interferometer

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Chinese Physics C 2009年第10期33卷 901-904页

作者：林栩凌张建兵雒峰卑华陆善良俞铁民戴志敏 Shanghai Institute of Applied Physics Chinese Academy of Sciences Graduate University of Chinese academy of sciences

Based on the femtosecond accelerator device which was built at the Shanghai Institute of Applied Physics （SINAP）, recently a modified far infrared Michelson interferometer has been developed to measure the length of electron bunches via the optical autocorrelation method. Compared with our former normal Michelson interferometer, we use a hollow retroreflector instead of a flat mirror as the reflective mirror. The experimental setup and results of the bunch length measurement will be described in this paper.

关键词： femtosecond linear accelerator bunch length interferometer hollow retroreflector

New design for multi-crystal data collection at SSRF

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Nuclear Science and Techniques 2018年第2期29卷 48-56页

作者： Bing Li Sheng Huang Qiang-Yan Pan Min-Jun Li Huan Zhou Qi-Sheng Wang Feng Yu Bo Sun Jian-Qiao Chen Jian-Hua He Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese academy of sciences Beijing 100049China

Data collection with microcrystals at synchrotron radiation facilities is challenging because it is difficult to harvest and locate microcrystals. Moreover,microcrystals are sensitive to radiation damage; thus, typically, a complete data set cannot be obtained with a single microcrystal. Herein, we report a new method for data collection with multiple microcrystals having a crystal size ranging from 1 to 30 lm. This method is suitable for not only low-temperature(100 K) data collection but also room-temperature data collection. Thin Kapton membranes were used to capture multiple crystals simultaneously. The microcrystals were visible under an optical microscope and easily located because the membrane was transparent and sufficiently thin. The film was fixed to a bracket that was prepared using a three-dimensional printer. The bracket was fixed on a magnetic base via screwing and employed by the goniometer system for data collection. Multiple data sets of fatty acid-binding protein 4(FABP4) and lysozyme microcrystals were collected using this novel designed device. Finally, the structures of protein FABP4 and lysozyme were obtained from these data via the molecule replacement method. The data statistics reveal that this method provides a comparable result to traditional methods such as a nylon loop.

关键词： Kapton membrane Microcrystals Multicrystal data collection Protein structure

Locating the QCD critical end point through peaked baryon number susceptibilities along the freeze-out line

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Chinese Physics C 2018年第1期42卷 32-37页

作者：李志镔陈亦点李丹凝黄梅 Institute of High Energy Physics Chinese Academy of Sciences School of Physics sciences University of Chinese Academy of Sciences Department of Physics Jinan University Theoretical Physics Center for Science Facilities Chinese Academy of Sciences

We investigate the baryon number susceptibilities up to fourth order along different freeze-out lines in a holographic QCD model with a critical end point（CEP）, and we propose that the peaked baryon number susceptibilities along the freeze-out line can be used as a clean signature to locate the CEP in the QCD phase *** the temperature and baryon chemical potential plane, the cumulant ratio of the baryon number susceptibilities（up to fourth order） forms a ridge along the phase boundary, and develops a sword-shaped ＂mountain＂ standing upright around the CEP in a narrow and oblate region. The measurement of baryon number susceptibilities from heavy-ion collision experiments is along the freeze-out line. If the freeze-out line crosses the foot of the CEP mountain, then one can observe the peaked baryon number susceptibilities along the freeze-out line, and the kurtosis of the baryon number distributions has the highest magnitude. The data from the first phase of the beam energy scan program at the Relativistic Heavy Ion Collider indicates that there should be a peak of the kurtosis of the baryon number distribution at a collision energy of around 5 Ge V, which suggests that the freeze-out line crosses the foot of the CEP mountain and the summit of the CEP should be located nearby, around a collision energy of 3–7 GeV.

关键词： QCD baryon number susceptibilities critical end point phase transition

Rational design and functional evolution of targeted peptides for bioanalytical applications

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Science China Chemistry 2016年第10期59卷 1250-1257页

作者： Yanyan Huang Yulong Jin Rui Zhao Beijing National Laboratory for Molecular sciences CAS Key Laboratory of Analytical Chemistry for Living BiosystemsInstitute of Chemistry Chinese Academy of Sciences University of Chinese academy of sciences

The complicated, highly dynamic and diverse nature of biosystems brings great challenges to the specific analysis of molecular processes of interest. Nature provides antibodies for the specific recognition of antigens, which is a straight-forward way for targeted analysis. However, there are still limitations during the practical applications due to the big size of the antibodies, which accelerate the discovery of small molecular probes. Peptides built from various optional building blocks and easily achieved by chemical synthetic approaches with predictable conformations, are versatile and can act as tailor-made targeting *** this mini review, we summarize the recent developments in the discovery of novel peptides for bioanalytical and biomedical applications. Progresses in peptide-library design and selection strategies are presented. Recent achievements in the peptide-guided detection, imaging and disease treatment are also focused.

关键词： peptide design screening targeted analysis biomedical applications

Effects of the properties of Mg(OH)_(2)precursor on the hydrothermal synthesis of magnesium oxysulfate whiskers

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Particuology 2024年第9期92卷 13-23页

作者： Thanayos Boonrit Mei Yang Guangwen Chen Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian116023China University of Chinese academy of sciences Beijing100049China

Magnesium oxysulfate(MOS)whiskers are commonly synthesized through a dissolution-precipitation mechanism,wherein Mg(OH)_(2)dissolves to form Mg(OH)_(6)^(4−),followed by reactions with SO_(4)^(2−)and H_(2)O to yield MOS ***,the impact of Mg(OH)_(2)precursor properties on the formation process of MOS whiskers has been insufficiently explored,and sector-like and needle-like morphologies were both observed in previous *** this study,we systematically investigated how the properties of Mg(OH)_(2)precursors influenced the crystalline structure and morphology of MOS *** various experimental conditions,MgSO_(4)·5Mg(OH)_(2)·2H_(2)O(152MOS)whiskers were consistently obtained,regardless of Mg(OH)_(2)morphology and *** size of Mg(OH)_(2)emerged as a critical factor in shaping the morphology of 152MOS ***-sized Mg(OH)_(2)(≤106±37 nm)favored the formation of sector-like whiskers,while larger-sized Mg(OH)_(2)(≥206±98 nm)encouraged the development of needle-like *** distinction was attributed to the slower dissolution rate exhibited by larger-sized Mg(OH)_(2),maintaining a smaller number of 152MOS nuclei and promoting the growth of needle-like whiskers instead of the aggregation of 152MOS nuclei into sector-like *** addition,the effects of the molar ratio of Mg^(2+)to SO_(4)^(2−)and hydrothermal temperature were also *** average length and diameter of the needle-like whiskers prepared with Mg(OH)_(2)of 331±145 nm under optimized conditions were 77±32 and 0.39±0.10μm,*** study presented an effective strategy for controlling the morphology of 152MOS whiskers.

关键词： Magnesium oxysulfate whiskers Morphology control Precursor Microreactor